Tungsten dioxo complex WO 2(C 9H 6NO) 2 was obtained via the low temperature solid-state reaction of(NH 4) 2WS 4, 8-hydroxyquinoline(8-hq) and(CH 3) 4NI, and it was characterized by means of elemental analyse...Tungsten dioxo complex WO 2(C 9H 6NO) 2 was obtained via the low temperature solid-state reaction of(NH 4) 2WS 4, 8-hydroxyquinoline(8-hq) and(CH 3) 4NI, and it was characterized by means of elemental analyses, IR spectroscopy and X-ray diffraction analysis. The crystal of the title compound belongs to monoclinic, space group C2/c, with the crystal cell parameters: a=1.3316(3) nm, b=0.94444(19) nm, c=1.3485(3) nm, β=109.66(3)°, V=1.5970(6) nm 3, Z=6. The title compound possesses a supramolecular structure formed through hydrogen bonds and π-π stacking interactions. The third-order non-linear optical(NLO) properties of the title compound were also investigated. The third-order non-linear absorption coefficient α 2 and refractive index n 2 are 0.85×10 -11 m/W -1 and -1.5×10 -19 m 2/W, respectively. The third-order non-linear susceptibility χ (3) is 3.03×10 -13 esu for 3.8×10 -5 mol/L sample concentration.展开更多
This review highlights the recent applications of non-linear optical(NLO)microscopy to study obesity-related health risks.A strong emphasis is given to the applications of coherent anti-Stokes Raman scattering(CARS)mi...This review highlights the recent applications of non-linear optical(NLO)microscopy to study obesity-related health risks.A strong emphasis is given to the applications of coherent anti-Stokes Raman scattering(CARS)microscopy where multiple non-linear optical imaging modalities including CARS,sum-frequency generation(SFG),and two-photon fluorescence are employed simultaneously on a single microscope platform.Specific examples on applications of NLO microscopy to study lipid-droplet biology,obesity-cancer relationship,atherosclerosis,and lipidrich biological structures are discussed.展开更多
The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)(4)) has been synthesized and its structure has been determined. It belongs to tetragonal system, I (4) over bar space group. The cell dimensions are: a ...The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)(4)) has been synthesized and its structure has been determined. It belongs to tetragonal system, I (4) over bar space group. The cell dimensions are: a = 1.1324 (3) nm, c = 0.4270 (2) nm, V = 0.5475 (3) nm(3), Z = 2, D-c = 2.959 g/cm(3), R = 0.028, R-w = 0.037. The structure feature of the crystal is the Hg-S-C=N-Mn bridge which leads to the formation of an infinite three dimensional network. Irradiated by a 1064 nm Nd:YAG laser beam, MnHg (SCN), shows a 532 nm second harmonic intensity which is 18 times as that of organic nonlinear optical crystal urea, and therefore shows a quite promising application value as a useful nonliear optical material.展开更多
Organic non-linear optical crystal diphenyl urea with molecular formula C13H12N2O was synthesized and grown successfully by slow evaporation solution growth technique. The single crystal X-ray diffraction (XRD) confir...Organic non-linear optical crystal diphenyl urea with molecular formula C13H12N2O was synthesized and grown successfully by slow evaporation solution growth technique. The single crystal X-ray diffraction (XRD) confirms that it crystallizes in orthorhombic crystal system with non-centrosymmetric space group Pna21. The various functional groups were identified qualitatively by Fourier transform-infra red (FT-IR) and FT-Raman techniques. The electron absorption spectrum was studied by UV-Vis spectrophotometer. Thermal behavior of the crystal was evidenced by thermogravimetric (TG) and differential scanning calorimetric (DSC) analyses. From DSC the melt ing point of the crystal is found to be 145°C. The existence of second harmonic generation (SHG) signal was evidenced using Kurtz Perry powder test and the efficiency of the crystal was found to be 0.64 times that of the standard KDP crystal.展开更多
An organic nonlinear optical (NLO) single crystal has been synthesized by slow solvent evaporation technique from aqueous solutions of L-serine and sodium fluoride (NaF) at ambient temperature. The grown crystal was c...An organic nonlinear optical (NLO) single crystal has been synthesized by slow solvent evaporation technique from aqueous solutions of L-serine and sodium fluoride (NaF) at ambient temperature. The grown crystal was confirmed by single crystal X-ray diffraction analysis. The powder X-ray diffraction of the grown crystal was recorded and indexed. The functional groups of the grown crystals were determined by FTIR spectrum. The optical absorption study reveals that the transparency of the crystal in the entire visible region and the lower edge was found to be 258 nm. Relative powder second harmonic generation (SHG) efficiency of the grown crystal was tested by Kurtz and Perry powder technique using high intensity Nd:YAG laser operating at 1064 nm.展开更多
In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exc...In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exchange correlation levels of theory. The vibrational frequencies of DMACB in the ground state have been calculated by using Hartree Fock level and density functional method (B3LYP/B3PW91) with 6-31G(d, p), basis set. Nonlinear optical (NLO) behavior of the examined molecule is investigated by the determination of the electric dipole moment μ, the polarizability α, and the hyperpolarizability β by using the B3LYP/B3PW91 methods.展开更多
Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks ...Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot material.We have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid interface.The structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was determined.The results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.展开更多
A defect diamond-like mid-IR NLO material,AgIn_(5)Se_(8),is synthesized and its NLO performance has been systematically studied for the first time.This compound exhibits a large SHG response about 0.7 times that of co...A defect diamond-like mid-IR NLO material,AgIn_(5)Se_(8),is synthesized and its NLO performance has been systematically studied for the first time.This compound exhibits a large SHG response about 0.7 times that of commercial AgGaS_(2).First-principles calculations reveal that the non-bonding electrons near the Se atoms make the dominant contribution to the SHG response.Furthermore,in order to improve the optical transparency range on a short-wave edge in AgIn_(5)Se_(8),material design is carried out to enlarge the band gap while keeping the strong SHG response.展开更多
Non-centrosymmetric semiconductors may exhibit non-linear optical(NLO)properties.For application-relevant materials,a careful balance of high second-harmonic generation(SHG)and high laser damage threshold(LDT)as well ...Non-centrosymmetric semiconductors may exhibit non-linear optical(NLO)properties.For application-relevant materials,a careful balance of high second-harmonic generation(SHG)and high laser damage threshold(LDT)as well as phase-matchability are required.We have previously identified(A)_(2)Cu_(2)Ge_(2)S_(14)(A=Y,La,Sm,and Gd)phases as promising NLO materials.Here,we developed a synthetic method to produce solid solution and high-entropy sulfides containing up to 9 elements.We report the synthesis,crystal structure,and NLO properties for solid solutions and high-entropy multi-metallic materials(HEMs)of the type(A)_(6)(TM)_(x)Ge_(2)S_(14)(A=La,Sm,Gd,mixture of(Y+La+Ce+Sm+Gd);TM=Mn,Cu;1≤x≤2).In this work,we establish that nearly all phases are phase matchable and the HEA composition with Cu possesses a SHG signal enhancement of 1.5×as compared to the AgGaS_(2)(AGS)standard for the largest particle size,as well as a LDT value of 2.8×of AGS.展开更多
The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly a...The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation.展开更多
In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the ...In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the extinction ratio(ER)reaches 28.8 dB at the wavelength of 1550 nm.The 3 dB bandwidth is greater than 150 nm.Within the 3 dB bandwidth,the ER is greater than 20.3 dB and 16.3 dB at bar and cross states,respectively.The power consumption for crystallization and amorphization of Sb_(2)Se_(3) is 105.86 nJ and 49 nJ,respectively.The switch holds significant promise for optical interconnects and optical computing applications.展开更多
We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature contr...We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature control.A shallow optical lattice with minimal tunneling minimizes AC Stark shifts.Phase-locked counter-propagating lattice beams and conductive vacuum viewports further reduce systematic uncertainties and a novel initial-state preparation method simplifies the system.Clock transition spectra achieve a linewidth of 2.5 Hz with a 400 ms clock pulse,and self-comparison stability reaches 5.1×10^(-16)at 1 s.These advancements give this clock the potential to be a critical platform for realizing outstanding systematic uncertainties in the future.展开更多
Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effect...Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making.展开更多
Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL abil...Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL ability across the visible to near-infrared-II spectra range remain scarce.Herein,a series of D-A typeπ-conjugated copolymers with ultra-narrow bandgaps(0.62-0.76 e V)and strong ICT absorption were synthesized by coupling electron-withdrawing block[1,2,5]thiadiazolo[3,4-g]quinoxaline(TQ)with various electron-donating groups(thiophene,selenophene,bithiophene,di(thiophen-2-yl)ethene,and thienothiophene for P1-P5,respectively).Z-scan experiments reveal that all copolymers exhibit RSA behaviours at both 532 and 1064 nm,while P1,P3 and P4 maintain RSA performance extending to 1600 nm.Among all copolymers,P5 exhibits the strongest RSA performance upon both 532 and 1064 nm laser pulses,with the highest nonlinear absorption coefficient(β_(eff))of 51.5 and 49.4 cm·GW^(-1),respectively,and the lowest OL onset fluence(Fon)of 0.31 and 0.38 J·cm^(-2),respectively.In contrast,P4 shows optimal RSA property at 1600 nm laser pulse,withβeff of 13.1 cm·GW^(-1)and Fon of 1.43 J·cm^(-2),respectively.Combining the results of Z-scan and UV-Vis-NIR experiments,it can be speculated that moderate ground-state absorption,rather than excessively strong absorption,favors superior RSA properties.This work offers valuable insights for designing copolymers with excellent RSA behavior,as well as presents a class of candidate material systems for ultrabroadband optical limiting.展开更多
AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopi...AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopic children.METHODS:AL,steep keratometry(K),flat K,posterior corneal keratometry(PK),total keratometry(TK),anterior chamber depth(ACD),horizontal corneal diameter(CD),and central corneal thickness(CCT)were obtained using IOL Master 700 and Pentacam AXL.The agreement between the devices was evaluated using intraclass correlation coefficients(ICC),Bland-Altman plots,and astigmatism vector analysis.RESULTS:Totally 175 myopic children(48.5%male)with a mean age of 10.29±2.14y were enrolled.The ICC and Bland-Altman plots indicated a satisfactory agreement for AL,ACD,and CCT.The mean difference in CD of-0.31±0.30 mm was considered clinically significant(>0.2 mm).Additionally,measurements of K and TK obtained from the IOL Master 700 showed good agreement.Nevertheless,there were clinically significant differences observed in PK,simulated keratometry(simK),total cornea power,and astigmatism(at least 10%of the cases with a difference of>10 degrees in meridian)between the two devices.CONCLUSION:The study findings demonstrate a significant difference in K,PK,astigmatism,and CD,indicating that the two optical biometers cannot be considered interchangeable.Therefore,it is recommended to utilize one kind device for follow-up examinations in myopic children.展开更多
Understanding the complex interplay between structured light and particles is crucial for unlocking advanced optical manipulation techniques.However,existing theories for optical force/torque are often limited to smal...Understanding the complex interplay between structured light and particles is crucial for unlocking advanced optical manipulation techniques.However,existing theories for optical force/torque are often limited to small particles within the dipole regime or specific light fields,thereby lacking universality and sometimes leading to ambiguity.To overcome these limitations,we establish a fully analytical and comprehensive framework for optical force/torque based on the Cartesian multipole expansion theory,which is applicable to arbitrary-sized bi-isotropic(chiral)spherical particles immersed in arbitrary monochromatic optical fields.Rigorous expressions are thus derived,which explicitly bridge the optical force/torque with particle-propertydependent coefficients and“force/torque source”quantities characterizing the incident light structures.Such quantities identify the ultimate physical origins of optical force/torque and are systematically classified into four categories based on their parity(P)and duality(D)symmetries.Each category interacts selectively with particles exhibiting specific P and D(a)symmetries,thus inducing distinct optical forces or torques with characteristic physical behaviors.This classification establishes the mutual symmetry-breaking criteria necessary for both particles and light beams to generate optical force/torque,offering a physics-based roadmap for engineering optical manipulations such as chirality sorting,light-driven micromotors,and beyond.展开更多
Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom a...Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.展开更多
Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accel...Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accelerator systems.This breakthrough opens up new possibilities for laboratory-scale light sources.All-optical inverse Compton scattering(AOCS)sources driven by LWFAs produce high-brightness,quasimonochromatic X rays with micrometer-scale source sizes,delivering the spatial coherence and resolution required for X-ray phase-contrast imaging(XPCI).These features position AOCS X-ray sources as promising tools for applications in biology,medicine,physics,and materials science.However,previous AOCS-based imaging studies have primarily focused on X-ray absorption imaging.In this work,we report successful experimental demonstrations of edge-enhanced in-line XPCI using energy-tunable,quasi-monochromatic AOCS X rays.With a spatial resolution of~20μm,our results clearly show the potential of high-resolution,AOCS-based XPCI applications.展开更多
Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly b...Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly becoming the preferred choice of physicians and patients for point-of-care testing due to its simplicity,cost-effectiveness,and rapid detection.Observing the optical signal change from the colloidal gold of the traditional LFIA strip has been widely applied for various biomarkers detection in body fluids.Despite the significant progress,rapid real-time detection of color changes in the colloidal gold by the naked eye still faces many limitations,such as large errors and the inability to quantify and accurately detect.New optical LFIA strip technology has emerged in recent years to extend its application scenarios for achieving quantitative detection such as fluorescence,afterglow,and chemiluminescence.Herein,we summarized the development of optical LFIA technology from single to hyphenated optical signals for biomarkers detection in body fluids from invasive and non-invasive sources.Moreover,the challenge and outlook of optical LFIA strip technology are highlighted to inspire the designing of next-generation diagnostic platforms.展开更多
Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior a...Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior and mechanical property of molecular crystals simultaneously via supramolecular salt strategy is rarely reported,which is very important to improve their photophysical behavior and softness for the fabrication of flexible light-emitting device.Herein,supramolecular salt approach has been successfully applied to synthesize two elastic organic fluorescent crystals(CMOH-Py-Cl and CMOH-Py-Br)derived from non-emissive and brittle pyridine-substituted coumarin derivative(CMOH-Py).Their elastic properties can be attributed to the prevalent presence of numerous weak interactions introduced by halogen atoms,which are beneficial to the absorption and release of mechanical energy.Furthermore,density functional theory(DFT)calculations demonstrated a narrowing of the HOMO-LUMO energy gaps from CMOH-Py to CMOH-Py-Cl/CMOH-Py-Br via supramolecular salt approach.Finally,the application of flexible crystal materials in the field of optical waveguides has been investigated.The transformation of crystals in terms of photophysical and mechanical properties,achieved by the supramolecular salt approach,offers novel insights into the design and construction of flexible crystalline materials,providing a new path for the development of next-generation smart materials.展开更多
基金the National Natural Science Foundation of China(No.2 0 2 710 2 1)
文摘Tungsten dioxo complex WO 2(C 9H 6NO) 2 was obtained via the low temperature solid-state reaction of(NH 4) 2WS 4, 8-hydroxyquinoline(8-hq) and(CH 3) 4NI, and it was characterized by means of elemental analyses, IR spectroscopy and X-ray diffraction analysis. The crystal of the title compound belongs to monoclinic, space group C2/c, with the crystal cell parameters: a=1.3316(3) nm, b=0.94444(19) nm, c=1.3485(3) nm, β=109.66(3)°, V=1.5970(6) nm 3, Z=6. The title compound possesses a supramolecular structure formed through hydrogen bonds and π-π stacking interactions. The third-order non-linear optical(NLO) properties of the title compound were also investigated. The third-order non-linear absorption coefficient α 2 and refractive index n 2 are 0.85×10 -11 m/W -1 and -1.5×10 -19 m 2/W, respectively. The third-order non-linear susceptibility χ (3) is 3.03×10 -13 esu for 3.8×10 -5 mol/L sample concentration.
基金supported by a post-doctoral fellowship F32HL089074 to Le T.T.,a NSF grant 0416785-MCB,NIH grants R21 EB004966,and R01 EB007243 to Cheng J.X.
文摘This review highlights the recent applications of non-linear optical(NLO)microscopy to study obesity-related health risks.A strong emphasis is given to the applications of coherent anti-Stokes Raman scattering(CARS)microscopy where multiple non-linear optical imaging modalities including CARS,sum-frequency generation(SFG),and two-photon fluorescence are employed simultaneously on a single microscope platform.Specific examples on applications of NLO microscopy to study lipid-droplet biology,obesity-cancer relationship,atherosclerosis,and lipidrich biological structures are discussed.
文摘The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)(4)) has been synthesized and its structure has been determined. It belongs to tetragonal system, I (4) over bar space group. The cell dimensions are: a = 1.1324 (3) nm, c = 0.4270 (2) nm, V = 0.5475 (3) nm(3), Z = 2, D-c = 2.959 g/cm(3), R = 0.028, R-w = 0.037. The structure feature of the crystal is the Hg-S-C=N-Mn bridge which leads to the formation of an infinite three dimensional network. Irradiated by a 1064 nm Nd:YAG laser beam, MnHg (SCN), shows a 532 nm second harmonic intensity which is 18 times as that of organic nonlinear optical crystal urea, and therefore shows a quite promising application value as a useful nonliear optical material.
文摘Organic non-linear optical crystal diphenyl urea with molecular formula C13H12N2O was synthesized and grown successfully by slow evaporation solution growth technique. The single crystal X-ray diffraction (XRD) confirms that it crystallizes in orthorhombic crystal system with non-centrosymmetric space group Pna21. The various functional groups were identified qualitatively by Fourier transform-infra red (FT-IR) and FT-Raman techniques. The electron absorption spectrum was studied by UV-Vis spectrophotometer. Thermal behavior of the crystal was evidenced by thermogravimetric (TG) and differential scanning calorimetric (DSC) analyses. From DSC the melt ing point of the crystal is found to be 145°C. The existence of second harmonic generation (SHG) signal was evidenced using Kurtz Perry powder test and the efficiency of the crystal was found to be 0.64 times that of the standard KDP crystal.
文摘An organic nonlinear optical (NLO) single crystal has been synthesized by slow solvent evaporation technique from aqueous solutions of L-serine and sodium fluoride (NaF) at ambient temperature. The grown crystal was confirmed by single crystal X-ray diffraction analysis. The powder X-ray diffraction of the grown crystal was recorded and indexed. The functional groups of the grown crystals were determined by FTIR spectrum. The optical absorption study reveals that the transparency of the crystal in the entire visible region and the lower edge was found to be 258 nm. Relative powder second harmonic generation (SHG) efficiency of the grown crystal was tested by Kurtz and Perry powder technique using high intensity Nd:YAG laser operating at 1064 nm.
文摘In the present study, structural properties of 4,4’ dimethylaminocyanobiphenyl (DMACB) have been studied extensively by using ab initio Hartree Fock (HF) and density functional theory (DFT) employing B3LYP/B3PW91 exchange correlation levels of theory. The vibrational frequencies of DMACB in the ground state have been calculated by using Hartree Fock level and density functional method (B3LYP/B3PW91) with 6-31G(d, p), basis set. Nonlinear optical (NLO) behavior of the examined molecule is investigated by the determination of the electric dipole moment μ, the polarizability α, and the hyperpolarizability β by using the B3LYP/B3PW91 methods.
文摘Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)method.The temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot material.We have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid interface.The structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(Eg),refractive index n,oscillating energy(Eo),dispersion energy(Ed),volume energy loss function(VELF),and surface energy loss function(SELF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was determined.The results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.
基金supported by the National Natural Science Foundation of China(Grant No.22133004 and 22275201)support of the Youth Innovation Promotion Association CAS.
文摘A defect diamond-like mid-IR NLO material,AgIn_(5)Se_(8),is synthesized and its NLO performance has been systematically studied for the first time.This compound exhibits a large SHG response about 0.7 times that of commercial AgGaS_(2).First-principles calculations reveal that the non-bonding electrons near the Se atoms make the dominant contribution to the SHG response.Furthermore,in order to improve the optical transparency range on a short-wave edge in AgIn_(5)Se_(8),material design is carried out to enlarge the band gap while keeping the strong SHG response.
基金supported by the Ames National Laboratory's Laboratory Directed Research and Development(LDRD)program(G.A.,N.W.H.,G.V.,and K.K.)N.W.H.was supported by the U.S.Department of Energy Office of Science,Science Undergraduate Laboratory Internships(SULI)+2 种基金The Ames National Laboratory is operated for the U.S.DOE by Iowa State University under contract#DE-AC02-07CH11358We thank Prof.V.Pecharsky(deceased)(ISU and Ames National Laboratory)for access to the arc-melting setup and Professor Javier Vela(ISU)for the use of the diffuse-reflectance setupThis manuscript is dedicated in loving memory of Dina Akopova,the grandmother of Dr.Georgiy Akopov.
文摘Non-centrosymmetric semiconductors may exhibit non-linear optical(NLO)properties.For application-relevant materials,a careful balance of high second-harmonic generation(SHG)and high laser damage threshold(LDT)as well as phase-matchability are required.We have previously identified(A)_(2)Cu_(2)Ge_(2)S_(14)(A=Y,La,Sm,and Gd)phases as promising NLO materials.Here,we developed a synthetic method to produce solid solution and high-entropy sulfides containing up to 9 elements.We report the synthesis,crystal structure,and NLO properties for solid solutions and high-entropy multi-metallic materials(HEMs)of the type(A)_(6)(TM)_(x)Ge_(2)S_(14)(A=La,Sm,Gd,mixture of(Y+La+Ce+Sm+Gd);TM=Mn,Cu;1≤x≤2).In this work,we establish that nearly all phases are phase matchable and the HEA composition with Cu possesses a SHG signal enhancement of 1.5×as compared to the AgGaS_(2)(AGS)standard for the largest particle size,as well as a LDT value of 2.8×of AGS.
基金funding from the National Key Research and Development Program of China(2021YFF0502900)special fund for Research on the National Major Research Instruments of China(62027824)+2 种基金the National Natural Science Foundation of China(U24A20314)the Key Research and Development Program of Anhui Province in China(2022a05020028)the Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province.
文摘The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation.
基金Supported by the National Natural Science Foundation of China(62204250)Autonomous deployment project of State Key Laboratory of Materials for Integrated Circuits(SKLJC-Z2024-A05).
文摘In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the extinction ratio(ER)reaches 28.8 dB at the wavelength of 1550 nm.The 3 dB bandwidth is greater than 150 nm.Within the 3 dB bandwidth,the ER is greater than 20.3 dB and 16.3 dB at bar and cross states,respectively.The power consumption for crystallization and amorphization of Sb_(2)Se_(3) is 105.86 nJ and 49 nJ,respectively.The switch holds significant promise for optical interconnects and optical computing applications.
基金supported by the Innovation Pro-gram for Quantum Science and Technology(Grant Nos.2021ZD0300900 and 2021ZD0300902)the Strate-gic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB35010202)the Operation and Maintenance of Major Scientific and Technological In-frastructure of the Chinese Academy of Sciences(Grant No.2024000014).
文摘We report the SrII optical lattice clock at the National Time Service Center(NTSC).In this system,a blackbody radiation shield with movable lattice mitigates blackbody radiation shifts through active temperature control.A shallow optical lattice with minimal tunneling minimizes AC Stark shifts.Phase-locked counter-propagating lattice beams and conductive vacuum viewports further reduce systematic uncertainties and a novel initial-state preparation method simplifies the system.Clock transition spectra achieve a linewidth of 2.5 Hz with a 400 ms clock pulse,and self-comparison stability reaches 5.1×10^(-16)at 1 s.These advancements give this clock the potential to be a critical platform for realizing outstanding systematic uncertainties in the future.
基金supported by the financial support received from the Indian Council of Medical Research-Department of Health Research(ICMRDHR-CoE-5/3/8/5/2019/I-MDMS)Medical Device and Diagnostics Mission Secretariat(MDMS)and Foundation for Centre for Healthcare Entrepreneurship(CfHE).
文摘Gastric cancer,including stomach tumors,poses significant health challenges due to late-stage diagnosis and limited early detection methods.Accurate imaging and precise tumor margin demarcation are critical for effective treatment planning and improved patient outcomes.Conventional imaging techniques,such as endoscopy and histopathology,provide valuable diagnostic information but cannot offer real-time assessment.We aim to explore the application of optical coherence tomography(OCT),combined with statistical and machine learning methods,for rapid tumor margin demarcation in gastrointestinal(GI)cancer tissues in exvivo.GI tumor specimens from 17 patients were imaged intraoperatively with OCT.Quantitative features were extracted from the images,and statistical and machine learning analyses were applied to distinguish tissue types.Subsequent histopathological evaluation was used as the reference standard for validation.The combination of OCT imaging and data-driven analysis enables clear differentiation between healthy,marginal and tumor tissues in near real-time.The KNN model achieved the highest classification accuracy(0.921±0.040),with SVM(0.906±0.038)and Extra Trees(0.901±0.034)also demonstrating robust performance in discriminating tissue margins.OCT findings demonstrate strong agreement with histopathology.Integrated with statistical and machine learning techniques,OCT enables rapid assessment of GI tumor margins.This approach provides quantitative objectivity and real-time feedback,closely approximating histopathological analysis and supporting improved surgical decision-making.
基金supported by the National Natural Science Foundation of China(No.52102013)。
文摘Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL ability across the visible to near-infrared-II spectra range remain scarce.Herein,a series of D-A typeπ-conjugated copolymers with ultra-narrow bandgaps(0.62-0.76 e V)and strong ICT absorption were synthesized by coupling electron-withdrawing block[1,2,5]thiadiazolo[3,4-g]quinoxaline(TQ)with various electron-donating groups(thiophene,selenophene,bithiophene,di(thiophen-2-yl)ethene,and thienothiophene for P1-P5,respectively).Z-scan experiments reveal that all copolymers exhibit RSA behaviours at both 532 and 1064 nm,while P1,P3 and P4 maintain RSA performance extending to 1600 nm.Among all copolymers,P5 exhibits the strongest RSA performance upon both 532 and 1064 nm laser pulses,with the highest nonlinear absorption coefficient(β_(eff))of 51.5 and 49.4 cm·GW^(-1),respectively,and the lowest OL onset fluence(Fon)of 0.31 and 0.38 J·cm^(-2),respectively.In contrast,P4 shows optimal RSA property at 1600 nm laser pulse,withβeff of 13.1 cm·GW^(-1)and Fon of 1.43 J·cm^(-2),respectively.Combining the results of Z-scan and UV-Vis-NIR experiments,it can be speculated that moderate ground-state absorption,rather than excessively strong absorption,favors superior RSA properties.This work offers valuable insights for designing copolymers with excellent RSA behavior,as well as presents a class of candidate material systems for ultrabroadband optical limiting.
基金Supported by National Natural Science Foundation of Guangdong,China(No.2020A1515010829,No.2023A1515011652,No.2025A1515012389)Science and Technology Program of Guangzhou,China(No.2025A03J4033).
文摘AIM:To evaluate the agreement of axial length(AL),anterior chamber parameters,and total cornea power obtained by swept-source optical coherence tomography(SS-OCT)-based and Scheimpflug-based optical biometers in myopic children.METHODS:AL,steep keratometry(K),flat K,posterior corneal keratometry(PK),total keratometry(TK),anterior chamber depth(ACD),horizontal corneal diameter(CD),and central corneal thickness(CCT)were obtained using IOL Master 700 and Pentacam AXL.The agreement between the devices was evaluated using intraclass correlation coefficients(ICC),Bland-Altman plots,and astigmatism vector analysis.RESULTS:Totally 175 myopic children(48.5%male)with a mean age of 10.29±2.14y were enrolled.The ICC and Bland-Altman plots indicated a satisfactory agreement for AL,ACD,and CCT.The mean difference in CD of-0.31±0.30 mm was considered clinically significant(>0.2 mm).Additionally,measurements of K and TK obtained from the IOL Master 700 showed good agreement.Nevertheless,there were clinically significant differences observed in PK,simulated keratometry(simK),total cornea power,and astigmatism(at least 10%of the cases with a difference of>10 degrees in meridian)between the two devices.CONCLUSION:The study findings demonstrate a significant difference in K,PK,astigmatism,and CD,indicating that the two optical biometers cannot be considered interchangeable.Therefore,it is recommended to utilize one kind device for follow-up examinations in myopic children.
基金supported by the National Natural Science Foundation of China(Grant Nos.12204117,12564043,12174076,12074084,and 12074169)the Guangxi Science and Technology Project(Grant Nos.2023GXNSFFA026002,2024GXNSFBA010261,2021GXNSFDA196001,and AD23026117)+3 种基金the Open Project of State Key Laboratory of Surface Physics in Fudan University(Grant No.KF2022_15)the Guangdong Province Talent Recruitment Program(Grant No.2021QN02C103)supported by the Research Grants Council of Hong Kong(Grant Nos.16310422 and AoE/P-502/20)the Innovation Project of Guangxi Graduate Education(Grant No.11241018)。
文摘Understanding the complex interplay between structured light and particles is crucial for unlocking advanced optical manipulation techniques.However,existing theories for optical force/torque are often limited to small particles within the dipole regime or specific light fields,thereby lacking universality and sometimes leading to ambiguity.To overcome these limitations,we establish a fully analytical and comprehensive framework for optical force/torque based on the Cartesian multipole expansion theory,which is applicable to arbitrary-sized bi-isotropic(chiral)spherical particles immersed in arbitrary monochromatic optical fields.Rigorous expressions are thus derived,which explicitly bridge the optical force/torque with particle-propertydependent coefficients and“force/torque source”quantities characterizing the incident light structures.Such quantities identify the ultimate physical origins of optical force/torque and are systematically classified into four categories based on their parity(P)and duality(D)symmetries.Each category interacts selectively with particles exhibiting specific P and D(a)symmetries,thus inducing distinct optical forces or torques with characteristic physical behaviors.This classification establishes the mutual symmetry-breaking criteria necessary for both particles and light beams to generate optical force/torque,offering a physics-based roadmap for engineering optical manipulations such as chirality sorting,light-driven micromotors,and beyond.
基金supported by the National Natural Science Foundation of China (Grant No.92576208)Tsinghua University Initiative Scientific Research Program+1 种基金Beijing Science and Technology Planning ProjectTsinghua University Dushi Program。
文摘Scalability remains a major challenge in building practical fault-tolerant quantum computers.Currently,the largest number of qubits achieved across leading quantum platforms ranges from hundreds to thousands.In atom arrays,scalability is primarily constrained by the capacity to generate large numbers of optical tweezers,and conventional techniques using acousto-optic deflectors or spatial light modulators struggle to produce arrays much beyond∼10,000 tweezers.Moreover,these methods require additional microscope objectives to focus the light into micrometer-sized spots,which further complicates system integration and scalability.Here,we demonstrate the experimental generation of an optical tweezer array containing 280×280 spots using a metasurface,nearly an order of magnitude more than most existing systems.The metasurface leverages a large number of subwavelength phase-control pixels to engineer the wavefront of the incident light,enabling both large-scale tweezer generation and direct focusing into micron-scale spots without the need for a microscope.This result shifts the scalability bottleneck for atom arrays from the tweezer generation hardware to the available laser power.Furthermore,the array shows excellent intensity uniformity exceeding 90%,making it suitable for homogeneous single-atom loading and paving the way for trapping arrays of more than 10,000 atoms in the near future.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0530000)the Discipline Construction Foundation of“Double World-class Project”.
文摘Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accelerator systems.This breakthrough opens up new possibilities for laboratory-scale light sources.All-optical inverse Compton scattering(AOCS)sources driven by LWFAs produce high-brightness,quasimonochromatic X rays with micrometer-scale source sizes,delivering the spatial coherence and resolution required for X-ray phase-contrast imaging(XPCI).These features position AOCS X-ray sources as promising tools for applications in biology,medicine,physics,and materials science.However,previous AOCS-based imaging studies have primarily focused on X-ray absorption imaging.In this work,we report successful experimental demonstrations of edge-enhanced in-line XPCI using energy-tunable,quasi-monochromatic AOCS X rays.With a spatial resolution of~20μm,our results clearly show the potential of high-resolution,AOCS-based XPCI applications.
基金supported by the National Natural Science Foundation of China (Nos.22234005,22494632,22404081)the Natural Science Foundation of Jiangsu Province (Nos.BK20222015,BK20240534)。
文摘Detecting biomarkers in body fluids by optical lateral flow immune assay(LFIA) technology provides rapid access to disease information for early diagnosis.LFIA is based on an antigen-antibody reaction and is rapidly becoming the preferred choice of physicians and patients for point-of-care testing due to its simplicity,cost-effectiveness,and rapid detection.Observing the optical signal change from the colloidal gold of the traditional LFIA strip has been widely applied for various biomarkers detection in body fluids.Despite the significant progress,rapid real-time detection of color changes in the colloidal gold by the naked eye still faces many limitations,such as large errors and the inability to quantify and accurately detect.New optical LFIA strip technology has emerged in recent years to extend its application scenarios for achieving quantitative detection such as fluorescence,afterglow,and chemiluminescence.Herein,we summarized the development of optical LFIA technology from single to hyphenated optical signals for biomarkers detection in body fluids from invasive and non-invasive sources.Moreover,the challenge and outlook of optical LFIA strip technology are highlighted to inspire the designing of next-generation diagnostic platforms.
基金supported by the National Natural Science Foundation of China(Nos.22205105,61874053,22075136)National Key Basic Research Program of China(No.2020YFA0709900)Jiangsu Provincial Postgraduate Scientific Research Innovation Program(No.KYCX24_1649).
文摘Improving the optoelectronic behavior and stress-deformation stability of conjugated materials is crucial for the realization of their potential applications in flexible optoelectronics.To tune the emission behavior and mechanical property of molecular crystals simultaneously via supramolecular salt strategy is rarely reported,which is very important to improve their photophysical behavior and softness for the fabrication of flexible light-emitting device.Herein,supramolecular salt approach has been successfully applied to synthesize two elastic organic fluorescent crystals(CMOH-Py-Cl and CMOH-Py-Br)derived from non-emissive and brittle pyridine-substituted coumarin derivative(CMOH-Py).Their elastic properties can be attributed to the prevalent presence of numerous weak interactions introduced by halogen atoms,which are beneficial to the absorption and release of mechanical energy.Furthermore,density functional theory(DFT)calculations demonstrated a narrowing of the HOMO-LUMO energy gaps from CMOH-Py to CMOH-Py-Cl/CMOH-Py-Br via supramolecular salt approach.Finally,the application of flexible crystal materials in the field of optical waveguides has been investigated.The transformation of crystals in terms of photophysical and mechanical properties,achieved by the supramolecular salt approach,offers novel insights into the design and construction of flexible crystalline materials,providing a new path for the development of next-generation smart materials.