Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imida...Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.展开更多
Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetra...Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetrahedral groups and triangular ones was proposed and implemented.Thus,a new semiorganic crystal,[C(NH_(2))_(3)]S_(3)O_(6)(G_(2)S_(3)O_(6)),was obtained,which is composed of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]+groups.It exhibits excellent optical properties with a short absorption cutoff edge of 218 nm,a strong NLO response of 1.4×KH_(2)PO_(4),and more especially,a large birefringence of 0.097@546 nm.This birefringence leap makes the G_(2)S_(3)O_(6) crystal achieve a phase-matching behavior under a 532 nm laser.Thus,the synergy of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]~+groups results in excellent optical performances.This finding opens a new horizon for exploring novel UV NLO crystals.展开更多
It remains highly challenging to achieve the high-order nonlinear optical(NLO)properties of atomically precise metal nanoclusters via template-maintained manipulation.Here,based on the M_(1)Ag_(24)(SR)_(18)(M=Ag/Au/Pt...It remains highly challenging to achieve the high-order nonlinear optical(NLO)properties of atomically precise metal nanoclusters via template-maintained manipulation.Here,based on the M_(1)Ag_(24)(SR)_(18)(M=Ag/Au/Pt/Pd;SR=2,4-dimethylthiophenol)cluster template,we demonstrated that the innermost kernel alloying rendered these nanoclusters highly controllable towards the nonlinear optics.The Pd-alloyed Pd_(1)Ag_(24)(SR)_(18) only dis-played single-photon-excited fluorescence,while the homo-silver Ag_(25)(SR)_(18) nanocluster generated the two-photonexcited fluorescence characterization.The Au-and Pt-doped M_(1)Ag_(24)(SR)_(18) nanoclusters showed high-order three-and four-photon-excited fluorescence,respectively,demonstrating that the order-by-order control over the nonlinear optics of nanoclusters has been accomplished.Moreover,Pd_(1)Ag_(24)(SR)_(18) with high-order NLO characterization exhibited the best optical limiting performance under 1000 nm excitation,in agreement with its most prominent NLO property.Overall,this work presents an intriguing cluster template that enables successive order control over the nonlinear optics of atomically precise metal nanoclusters,hopefully paving the way for developing cluster-based nanomaterials with customized optical characterizations.展开更多
Short-wavelength nonlinear optical(NLO)crystals can convert a specific wavelength of light to ultraviolet(UV)and deep-UV region.To date,most of the commercialized UV and deep-UV NLO materials are borate crystals.By co...Short-wavelength nonlinear optical(NLO)crystals can convert a specific wavelength of light to ultraviolet(UV)and deep-UV region.To date,most of the commercialized UV and deep-UV NLO materials are borate crystals.By combining the merits of borates and silicates,borosilicates exhibit some unique advantages of rich structural types,moderate second harmonic generation(SHG)response,and high UV transmittance.This paper summarizes the known NLO borosilicates which can be grouped into two types according to the linkage modes of BO and SiO units:(1)borosilicates with BOSi covalent bond,and(2)borosilicates with isolated BO and SiO units.The structural features,SHG intensities,and UV cutoff edges of these borosilicates are discussed.Finally,future perspectives in this field are presented.展开更多
In this paper,the third-order nonlinear optical(NLO)properties of covalent organic framework(COF)materials with conjugated amphoteric ion structure are studied for the first time.A highly ordered crystalline ultrathin...In this paper,the third-order nonlinear optical(NLO)properties of covalent organic framework(COF)materials with conjugated amphoteric ion structure are studied for the first time.A highly ordered crystalline ultrathin films of the ionic COF material PySQ-iCOF was successfully fabricated using a solid-liquid interface method,meanwhile the building units extracted to be independent small molecule,1-PySA,were synthesized for comparative studies.Compared to 1-PySA,PySQ-iCOF possesses not only a larger conjugated system but also exhibits enhanced polarization and charge transfer capabilities.The NLO properties of PySQ-iCOF and the small molecule 1-PySA were investigated using Z-scan technique at a wavelength of 532 nm,revealing the PySQ-iCOF thin film exhibits outstanding NLO performance.Specifically,it demonstrates saturable absorption under nanosecond(ns)pulse laser irradiation(β=9.59×10^(-6) m/W),while exhibiting reverse saturable absorption under femtosecond(fs)pulse conditions(β=6.91×10^(-8) m/W).Furthermore,the PySQ-iCOF film exhibits strong negative refractive nonlinearity,−6×10^(-12) m^(2)/W for ns and -3.8×10^(-13) m^(2)/W for fs,respectively.Transient absorption spectroscopy studies indicate that the pulse-width-dependent nonlinear absorption char-acteristics of the PySQ-iCOF film originate from the generation of triplet excited states.Both nonlinear absorption coefficient and nonlinear refractive index of the PySQ-iCOF film surpass those of most reported organic materials measured under comparable conditions,which provides huge potential in all-optical manipulating and switching at the nanoscale as outstanding NLO materials.展开更多
The interactions of charge transfer(CT)and nonradiative energy transfer(ET)in heterojunctions of two-dimensional(2D)transition metal dichalcogenides and quasi-2D single crystal perovskite thin films have the potential...The interactions of charge transfer(CT)and nonradiative energy transfer(ET)in heterojunctions of two-dimensional(2D)transition metal dichalcogenides and quasi-2D single crystal perovskite thin films have the potential applications in sensor,energy harvesting and solar cells.However,the CT and ET between them are not clear.Herein,we examine the ET in a(PEA)_(2)PbI_(4)/WS_(2)(PEA stands for phenethylamine and(PEA)_(2)PbI_(4)is abbreviated as PEPI)heterojunction using combined ultrafast spectroscopy and nonlinear optical absorption measurements.The ET from PEPI to WS_(2)predicted by band alignment is first observed with photoluminescence spectroscopy and then revealed by femtosecond transient absorption spectroscopy to exhibit a high ET efficiency approximating 68%.展开更多
Diamond-like AgGaS_(2)(DL AGS),as the typical infrared nonlinear optical(IR NLO)material,has suffered from its intrinsic drawbacks like narrow band gap(E_(g))and low laser-induced damage threshold(LIDT).In this work,b...Diamond-like AgGaS_(2)(DL AGS),as the typical infrared nonlinear optical(IR NLO)material,has suffered from its intrinsic drawbacks like narrow band gap(E_(g))and low laser-induced damage threshold(LIDT).In this work,by first introducing[NaS_(8)]polyhedral unit into the A_(2)^(Ⅰ)Q^(Ⅵ)-Ag_(2)Q^(Ⅵ)-C_(2)^(Ⅲ)Q_(3)^(Ⅵ) system,a new Ag-based sulfide NaAg_(3)Ga_(8)S_(14) with diamond-like framework(DLF)has been successfully synthesized via a high-temperature solid-state method in experiment.The compound shows a wide Eg(~3.0 eV),high LIDT(3.0×AGS)and moderate phase-matching NLO response(~0.7×AGS),effectively balancing the E_(g)(≥3.0 eV)and NLO response(≥0.5×AGS),demonstrating its promise for IR NLO applications.Theoretical calculations elucidate the orbital hybridization between Na 3s,Ag 4d5s and S 3p enhances E_(g),and the aligned NLO-active units([AgS_(4)]and[GaS_(4)])induce moderate NLO response in the compound.These findings not only expand the chemical and structural diversities of Ag-based chalcogenides,but also provide effective strategies for designing DLF functional materials derived from diamond-like structures.展开更多
The time delay（TD） of femtoseeond pulses is studied for the first time, which generated from the nonlinear optical loop mirror composed of dispersion decreasing fiber（DDF-NOLM）. The results show that the higher-or...The time delay（TD） of femtoseeond pulses is studied for the first time, which generated from the nonlinear optical loop mirror composed of dispersion decreasing fiber（DDF-NOLM）. The results show that the higher-order dispersion and high order nonlinearities such as Raman frequency shift play a key role in producing TD, and that the time delay ean be suppressed by the third-order dispersion（TOD） in DDF-NOLM. The mechanism of the time delay suppression is also discussed in detail.展开更多
The interest in tailoring light in all its degrees of freedom is steadily gaining traction,driven by the tremendous developments in the toolkit for the creation,control and detection of what is now called structured l...The interest in tailoring light in all its degrees of freedom is steadily gaining traction,driven by the tremendous developments in the toolkit for the creation,control and detection of what is now called structured light.Because the complexity of these optical fields is generally understood in terms of interference,the tools have historically been linear optical elements that create the desired superpositions.For this reason,despite the long and impressive history of nonlinear optics,only recently has the spatial structure of light in nonlinear processes come to the fore.In this review we provide a concise theoretical framework for understanding nonlinear optics in the context of structured light,offering an overview and perspective on the progress made,and the challenges that remain.展开更多
A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by soluti...A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by solution growth method. The crystal was then characterized by X-ray diffraction structure analysis and second-harmonic generation(SHG)investigation. Polymorphous crystal forms of the MONA were grown from different solvents having different nonlinear optical properties depending on their different crystal structures. The relationship between the crystal growth and crystal structure is discusse.展开更多
Nonlinear optical(NLO)crystals can be employed to expand the laser frequency and thus are of technical importance in advanced laser science.Noncentrosymmetric rare earth compounds keep attracting broad interest as a s...Nonlinear optical(NLO)crystals can be employed to expand the laser frequency and thus are of technical importance in advanced laser science.Noncentrosymmetric rare earth compounds keep attracting broad interest as a significant branch of NLO materials because the highly distorted structural motifs centered by rare earth ions could remarkably benefit the second harmonic generation.In this review,we proceed from structure-properties relationship and reveal the role of rare earth element in the optical properties of NLO materials.We believe that this work can deepen the understanding of rare earth-based NLO materials and provide some enlightenment for exploring novel practical NLO crystals.展开更多
GaAs nanocrystals were prepared via a simple mechanical ball milling technique. The prepared GaAs nanocrystals have high purity and could form colloidal ethanol suspension without any surfactant additives. The colloid...GaAs nanocrystals were prepared via a simple mechanical ball milling technique. The prepared GaAs nanocrystals have high purity and could form colloidal ethanol suspension without any surfactant additives. The colloidal GaAs nanocrystal suspension displayed excellent two-photon absorption property over the visible and near-infrared region from 490 nm to 1064 nm, which enables it to become a promising broadband optical limiting material.展开更多
Dendrimers are considered as a promising family of organic second-order nonlinear optical （NLO） polymers because of their well-defined structures, easily modified peripheral functional groups, interior branches and ...Dendrimers are considered as a promising family of organic second-order nonlinear optical （NLO） polymers because of their well-defined structures, easily modified peripheral functional groups, interior branches and central cores. In order to obtain NLO materials with high performance, dendrimer structures have been optimized in the past years, such as the ＂branch only＂ and the ＂root containing＂ type dendrimers. This feature article highlights the achievements in exploring the rational design of dendrimers, partially marked by their macroscopic NLO performance.展开更多
This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-（2＇-hydroxyphenyl）benzothiazole （HBT） in ethanol solution...This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-（2＇-hydroxyphenyl）benzothiazole （HBT） in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer （ESIPT） effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.展开更多
Graphene has excellent thirdorder nonlinear optical(NLO)properties due to its unique electronic band structure and wideband gap tunability.This paper focuses on the research progress of graphene and its composite mate...Graphene has excellent thirdorder nonlinear optical(NLO)properties due to its unique electronic band structure and wideband gap tunability.This paper focuses on the research progress of graphene and its composite materials in nonlinear optics in recent years.In this review,recent results on graphene(or graphene oxide)-metal nanoparticles(G-MNPs),graphene-metal-oxide nanoparticles(G-MONPs),graphene-metal sulfide nanoparticles(G-MSNPs),and graphene-organic molecular composites(G-OM)have been discussed.In addition,the enhancement mechanism of nonlinear absorption(NLA)and optical limiting(OL)have also been covered.展开更多
zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is character...zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is characterized by using the X-ray Powder diffraction(XRPD) and infrared (IR) spectroscopy at room temperature. TheAbsorptions of intrinsic ions and ZCTC in a solution state arediscussed as well as Transmission properties of the ZCTC crystal. Aneffective method of reducing the surface Reflection loss of ZCTCcrystal is introduced.展开更多
The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective ma...The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective mass approximation, using the matrix diagonalization method and the compact density-matrix approach. The linear and nonlinear optical absorption coefficients between the ground （L =0） and the first excited state （L = 1） have been examined based on the computed energies and wave functions. We find that the linear, nonlinear third-order, and total optical absorption coefficients are strongly affected by the confinement strength of QDs, the external magnetic field, and the incident optical intensity.展开更多
The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two ...The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two non-centrosymmetric halidepnictides,[Cd_(2)P]_(2)[CdBr_(4)](CPB)and[Cd_(2)As]_(2)[CdBr_(4)](CAB) were reported.The complete octet binding electrons of pnictogens were constructed by four Cd-P pola covalent bonds under the anchoring effect of halogens,creating an extremely flat valence band maximum with band dispersion of only 0.17 eV.As expected,the balance of the covalency and ionicity in CPB and CAB was successfully realized,leading to a wide band gap of 2.58 eV and 1.88 eV.Remarkably,CPB no only has a widest band gap among Cd-containing pnictides,but also exhibits a SHG effect of 1.2×AgGaS_(2).moderate birefringence(0.088@visible light and calcd.0.043@2050 nm)and a wide IR transmission range.This is the first time that the octet binding electrons construction strategy was utilized to design non diamond like NLO pnictides with excellent performances.展开更多
A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemen...A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.展开更多
A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalen...A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by SEM, FTIR,H-1-NMR, UV-Vis, DSC and second harmonic generation (SHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic SiO2 networks induces low dipole alignment relaxation and preferable orientational stability. The SHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good SHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.展开更多
文摘Herein,we report the synthesis and third-order nonlinear optical(NLO)properties of a novel cage-based 2D metal-organic framework constructed from Ti_(4)L_(6)(L4-=embonate)cage combined with Mg^(2+)and tris[4-(1H-imidazol-1-yl)phenyl]amine(tipa)ligand,whose molecular formula is(Me_(2)CH_(2))_(2)[Mg_(3)(Ti_(4)L_(6))(tipa)(H_(2)O)_(12)](PTC‑378).The Ti_(4)L_(6)tetrahedral cages serve as robust building units,while the Mg^(2+)ions and tipa ligands provide structural stability and tunable optical properties.The resulting PTC‑378 film exhibited intriguing third-order NLO property,which was systematically investigated using Z-scan techniques.Our results demonstrate that the synergistic interaction between Ti_(4)L_(6)cages andπ-conjugated ligands significantly enhances the NLO performance of the materials.CCDC:2453909.
基金supported by the National Natural Science Foundation of China(Nos.52172009 and 12275274)the Science and Technology Project of Fujian Province(Nos.2021J01519 and 2021H0043)the Instrument Developing Project of Chinese Academy of Sciences(No.YJKYYQ20210033)。
文摘Sulfates are always promising short-wave ultraviolet(UV)nonlinear optical(NLO)candidates,if their birefringence could be greatly improved.Here,in terms of the insufficient birefringence,the unity of heteroleptic tetrahedral groups and triangular ones was proposed and implemented.Thus,a new semiorganic crystal,[C(NH_(2))_(3)]S_(3)O_(6)(G_(2)S_(3)O_(6)),was obtained,which is composed of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]+groups.It exhibits excellent optical properties with a short absorption cutoff edge of 218 nm,a strong NLO response of 1.4×KH_(2)PO_(4),and more especially,a large birefringence of 0.097@546 nm.This birefringence leap makes the G_(2)S_(3)O_(6) crystal achieve a phase-matching behavior under a 532 nm laser.Thus,the synergy of[S_(3)O_(6)]^(2-)and[C(NH_(2))_(3)]~+groups results in excellent optical performances.This finding opens a new horizon for exploring novel UV NLO crystals.
基金the NSFC(U24A20480,22371003,22471001,22475002)the Ministry of Education,Natural Science Foundation of Anhui Province(2408085Y006)the Scientific Research Program of Universities in Anhui Province(2022AH030009).
文摘It remains highly challenging to achieve the high-order nonlinear optical(NLO)properties of atomically precise metal nanoclusters via template-maintained manipulation.Here,based on the M_(1)Ag_(24)(SR)_(18)(M=Ag/Au/Pt/Pd;SR=2,4-dimethylthiophenol)cluster template,we demonstrated that the innermost kernel alloying rendered these nanoclusters highly controllable towards the nonlinear optics.The Pd-alloyed Pd_(1)Ag_(24)(SR)_(18) only dis-played single-photon-excited fluorescence,while the homo-silver Ag_(25)(SR)_(18) nanocluster generated the two-photonexcited fluorescence characterization.The Au-and Pt-doped M_(1)Ag_(24)(SR)_(18) nanoclusters showed high-order three-and four-photon-excited fluorescence,respectively,demonstrating that the order-by-order control over the nonlinear optics of nanoclusters has been accomplished.Moreover,Pd_(1)Ag_(24)(SR)_(18) with high-order NLO characterization exhibited the best optical limiting performance under 1000 nm excitation,in agreement with its most prominent NLO property.Overall,this work presents an intriguing cluster template that enables successive order control over the nonlinear optics of atomically precise metal nanoclusters,hopefully paving the way for developing cluster-based nanomaterials with customized optical characterizations.
基金supported by the National Natural Science Foundation of China(No.21975224).
文摘Short-wavelength nonlinear optical(NLO)crystals can convert a specific wavelength of light to ultraviolet(UV)and deep-UV region.To date,most of the commercialized UV and deep-UV NLO materials are borate crystals.By combining the merits of borates and silicates,borosilicates exhibit some unique advantages of rich structural types,moderate second harmonic generation(SHG)response,and high UV transmittance.This paper summarizes the known NLO borosilicates which can be grouped into two types according to the linkage modes of BO and SiO units:(1)borosilicates with BOSi covalent bond,and(2)borosilicates with isolated BO and SiO units.The structural features,SHG intensities,and UV cutoff edges of these borosilicates are discussed.Finally,future perspectives in this field are presented.
基金the National Natural Science Foundation of China(22171076)Jing Li at the Technical Institute of Physics and Chemistry,Chinese Academy of Sciences(CAS),for his measurement of dynamic processes.
文摘In this paper,the third-order nonlinear optical(NLO)properties of covalent organic framework(COF)materials with conjugated amphoteric ion structure are studied for the first time.A highly ordered crystalline ultrathin films of the ionic COF material PySQ-iCOF was successfully fabricated using a solid-liquid interface method,meanwhile the building units extracted to be independent small molecule,1-PySA,were synthesized for comparative studies.Compared to 1-PySA,PySQ-iCOF possesses not only a larger conjugated system but also exhibits enhanced polarization and charge transfer capabilities.The NLO properties of PySQ-iCOF and the small molecule 1-PySA were investigated using Z-scan technique at a wavelength of 532 nm,revealing the PySQ-iCOF thin film exhibits outstanding NLO performance.Specifically,it demonstrates saturable absorption under nanosecond(ns)pulse laser irradiation(β=9.59×10^(-6) m/W),while exhibiting reverse saturable absorption under femtosecond(fs)pulse conditions(β=6.91×10^(-8) m/W).Furthermore,the PySQ-iCOF film exhibits strong negative refractive nonlinearity,−6×10^(-12) m^(2)/W for ns and -3.8×10^(-13) m^(2)/W for fs,respectively.Transient absorption spectroscopy studies indicate that the pulse-width-dependent nonlinear absorption char-acteristics of the PySQ-iCOF film originate from the generation of triplet excited states.Both nonlinear absorption coefficient and nonlinear refractive index of the PySQ-iCOF film surpass those of most reported organic materials measured under comparable conditions,which provides huge potential in all-optical manipulating and switching at the nanoscale as outstanding NLO materials.
基金financially supported by the National Natural Science Foundation of China(Nos.52472153,11704081,and 62175210)Guangxi Natural Science Foundation(No.2020GXNSFAA297182)the special fund for"Guangxi Bagui Scholars,"National Science and Technology Innovation Talent Cultivation Program(No.2023BZRC016)
文摘The interactions of charge transfer(CT)and nonradiative energy transfer(ET)in heterojunctions of two-dimensional(2D)transition metal dichalcogenides and quasi-2D single crystal perovskite thin films have the potential applications in sensor,energy harvesting and solar cells.However,the CT and ET between them are not clear.Herein,we examine the ET in a(PEA)_(2)PbI_(4)/WS_(2)(PEA stands for phenethylamine and(PEA)_(2)PbI_(4)is abbreviated as PEPI)heterojunction using combined ultrafast spectroscopy and nonlinear optical absorption measurements.The ET from PEPI to WS_(2)predicted by band alignment is first observed with photoluminescence spectroscopy and then revealed by femtosecond transient absorption spectroscopy to exhibit a high ET efficiency approximating 68%.
基金supported by the Tianshan Talent Training Program(2024TSYCLJ0035)the Natural Science Foundation of the Xinjiang Uygur Autonomous Region(2024D01E30,2025D01B157)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0880000)the Open Fund of the Anhui Key Laboratory of Photonic Materials and Devices(AHKL2024KF02)the National Natural Sci-ence Foundation of China(22475234,52402017)the support from Tianchi Doctor Plan of Xinjiang Uygur Autonomous Region.
文摘Diamond-like AgGaS_(2)(DL AGS),as the typical infrared nonlinear optical(IR NLO)material,has suffered from its intrinsic drawbacks like narrow band gap(E_(g))and low laser-induced damage threshold(LIDT).In this work,by first introducing[NaS_(8)]polyhedral unit into the A_(2)^(Ⅰ)Q^(Ⅵ)-Ag_(2)Q^(Ⅵ)-C_(2)^(Ⅲ)Q_(3)^(Ⅵ) system,a new Ag-based sulfide NaAg_(3)Ga_(8)S_(14) with diamond-like framework(DLF)has been successfully synthesized via a high-temperature solid-state method in experiment.The compound shows a wide Eg(~3.0 eV),high LIDT(3.0×AGS)and moderate phase-matching NLO response(~0.7×AGS),effectively balancing the E_(g)(≥3.0 eV)and NLO response(≥0.5×AGS),demonstrating its promise for IR NLO applications.Theoretical calculations elucidate the orbital hybridization between Na 3s,Ag 4d5s and S 3p enhances E_(g),and the aligned NLO-active units([AgS_(4)]and[GaS_(4)])induce moderate NLO response in the compound.These findings not only expand the chemical and structural diversities of Ag-based chalcogenides,but also provide effective strategies for designing DLF functional materials derived from diamond-like structures.
文摘The time delay（TD） of femtoseeond pulses is studied for the first time, which generated from the nonlinear optical loop mirror composed of dispersion decreasing fiber（DDF-NOLM）. The results show that the higher-order dispersion and high order nonlinearities such as Raman frequency shift play a key role in producing TD, and that the time delay ean be suppressed by the third-order dispersion（TOD） in DDF-NOLM. The mechanism of the time delay suppression is also discussed in detail.
文摘The interest in tailoring light in all its degrees of freedom is steadily gaining traction,driven by the tremendous developments in the toolkit for the creation,control and detection of what is now called structured light.Because the complexity of these optical fields is generally understood in terms of interference,the tools have historically been linear optical elements that create the desired superpositions.For this reason,despite the long and impressive history of nonlinear optics,only recently has the spatial structure of light in nonlinear processes come to the fore.In this review we provide a concise theoretical framework for understanding nonlinear optics in the context of structured light,offering an overview and perspective on the progress made,and the challenges that remain.
文摘A novel tolane 4-methoxy-4'-nitro-diphenyl-acetylene (MONA) has been prepared quantitatively by reacting cuprous p-methoxy phenyl-acetylene with p-iodonitrobenzene. A single crystal of the Moan was grown by solution growth method. The crystal was then characterized by X-ray diffraction structure analysis and second-harmonic generation(SHG)investigation. Polymorphous crystal forms of the MONA were grown from different solvents having different nonlinear optical properties depending on their different crystal structures. The relationship between the crystal growth and crystal structure is discusse.
基金Project supported by the National Natural Science Foundation of China(51972208,51832007)。
文摘Nonlinear optical(NLO)crystals can be employed to expand the laser frequency and thus are of technical importance in advanced laser science.Noncentrosymmetric rare earth compounds keep attracting broad interest as a significant branch of NLO materials because the highly distorted structural motifs centered by rare earth ions could remarkably benefit the second harmonic generation.In this review,we proceed from structure-properties relationship and reveal the role of rare earth element in the optical properties of NLO materials.We believe that this work can deepen the understanding of rare earth-based NLO materials and provide some enlightenment for exploring novel practical NLO crystals.
基金The work was financially supported by the National Natural Science Foundation of China (Nos. 10104003, 10204003, 90206003, and 90101027) and the National Key Basic Research Special Foundation of China (No.TG1999075207).
文摘GaAs nanocrystals were prepared via a simple mechanical ball milling technique. The prepared GaAs nanocrystals have high purity and could form colloidal ethanol suspension without any surfactant additives. The colloidal GaAs nanocrystal suspension displayed excellent two-photon absorption property over the visible and near-infrared region from 490 nm to 1064 nm, which enables it to become a promising broadband optical limiting material.
基金supported by the National Natural Science Foundation of China(No.21325416)
文摘Dendrimers are considered as a promising family of organic second-order nonlinear optical （NLO） polymers because of their well-defined structures, easily modified peripheral functional groups, interior branches and central cores. In order to obtain NLO materials with high performance, dendrimer structures have been optimized in the past years, such as the ＂branch only＂ and the ＂root containing＂ type dendrimers. This feature article highlights the achievements in exploring the rational design of dendrimers, partially marked by their macroscopic NLO performance.
基金Project supported by the National Natural Science Foundation of China （Grant No 60178025） and the Key Laboratory of 0ptoelectronics Information Technical Science of Ministry of Education, Institute of Modern 0ptics, Nankai University, China.
文摘This paper demonstrates an all-optical switching model system comprising a single pulsed pump beam at 355 nm and a CW He-Ne signal beam at 632.8 nm with 2-（2＇-hydroxyphenyl）benzothiazole （HBT） in ethanol solution. The origins of the optical switching effect were discussed. By the study of nonlinear optical properties for HBT in ethanol solvent, this paper verified that the excited-state intramolecular proton transfer （ESIPT） effect of HBT and the thermal effect of solvent worked on quite different time scales and together induced the change of the refractive index of HBT solution, leading to the signal beam deflection. The results indicated that the HBT molecule could be an excellent candidate for high-speed and high-sensitive optical switching devices.
基金Project supported by the National Natural Science Foundation of China(Grant No.11375136).
文摘Graphene has excellent thirdorder nonlinear optical(NLO)properties due to its unique electronic band structure and wideband gap tunability.This paper focuses on the research progress of graphene and its composite materials in nonlinear optics in recent years.In this review,recent results on graphene(or graphene oxide)-metal nanoparticles(G-MNPs),graphene-metal-oxide nanoparticles(G-MONPs),graphene-metal sulfide nanoparticles(G-MSNPs),and graphene-organic molecular composites(G-OM)have been discussed.In addition,the enhancement mechanism of nonlinear absorption(NLA)and optical limiting(OL)have also been covered.
文摘zinc cadmium thiocyanate (ZCTC), ZnCd(SCN)_4, has been discoveredas a UV second-order nonlinear optical coordination crystal. Titsthermal and transmission Properties are reported. The thermaldecomposition is characterized by using the X-ray Powder diffraction(XRPD) and infrared (IR) spectroscopy at room temperature. TheAbsorptions of intrinsic ions and ZCTC in a solution state arediscussed as well as Transmission properties of the ZCTC crystal. Aneffective method of reducing the surface Reflection loss of ZCTCcrystal is introduced.
基金supported by National Natural Science Foundation of China under Grant No.10775035
文摘The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective mass approximation, using the matrix diagonalization method and the compact density-matrix approach. The linear and nonlinear optical absorption coefficients between the ground （L =0） and the first excited state （L = 1） have been examined based on the computed energies and wave functions. We find that the linear, nonlinear third-order, and total optical absorption coefficients are strongly affected by the confinement strength of QDs, the external magnetic field, and the incident optical intensity.
基金supported by the National Natural Science Foundation of China(Nos.22305174,22375147,52332001,51890862,51902308 and 21921001)the Natural Science Foundation of Fujian Province(No.2021J05097)the Natural Science Foundation of Tianjin City(No.22JCYBJC01380)。
文摘The design of pnictide nonlinear optical crystals is quite different from chalcogenide and oxide those in which a new paradigm need be developed to regulate the band gap,one of key optical parameters In this work,two non-centrosymmetric halidepnictides,[Cd_(2)P]_(2)[CdBr_(4)](CPB)and[Cd_(2)As]_(2)[CdBr_(4)](CAB) were reported.The complete octet binding electrons of pnictogens were constructed by four Cd-P pola covalent bonds under the anchoring effect of halogens,creating an extremely flat valence band maximum with band dispersion of only 0.17 eV.As expected,the balance of the covalency and ionicity in CPB and CAB was successfully realized,leading to a wide band gap of 2.58 eV and 1.88 eV.Remarkably,CPB no only has a widest band gap among Cd-containing pnictides,but also exhibits a SHG effect of 1.2×AgGaS_(2).moderate birefringence(0.088@visible light and calcd.0.043@2050 nm)and a wide IR transmission range.This is the first time that the octet binding electrons construction strategy was utilized to design non diamond like NLO pnictides with excellent performances.
基金supported by National Natural Science Foundation of China(21401147)Basic Research Program of Natural Science from Shaanxi Provincial Government(2015JQ2032)+2 种基金Scientific Research Program from Education Department of Shaanxi Provincial Government(2013JK0654)Opening Foundation from State Key Laboratory of Coordination Chemistry in Nanjing University(201219)the Program for Distinguished Young Scholars of Xi’an Polytechnic University(201403)
文摘A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.
基金This work was supported by the Postdoctoral Science Foundation of Guangdong Province (No. 9644) and the Natural Science Fund of Guangdong Province(No. 990629).
文摘A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by SEM, FTIR,H-1-NMR, UV-Vis, DSC and second harmonic generation (SHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic SiO2 networks induces low dipole alignment relaxation and preferable orientational stability. The SHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good SHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.
