Self-pumped phase conjugation （SPPC） is completely self-contained and requires no external mirrors, pumping beams or applied electric fields. Because of its simplicity and high reflectivity, SPPC has a host of poten...Self-pumped phase conjugation （SPPC） is completely self-contained and requires no external mirrors, pumping beams or applied electric fields. Because of its simplicity and high reflectivity, SPPC has a host of potential applications including correcting spatial phase distortion, and optical image processing. At the present time, SPPC has been realized in BaTiO<sub>3</sub>, KNbO<sub>3</sub>, Ce-doped SBN and KNSBN single crystals. The KNSBN展开更多
Potassium sodium strontium barium niobate (KNSBN) crystal is one of the important photorefractive ferroelectric crystal materials, not only having good photorefractive properties, but also many advantages over other p...Potassium sodium strontium barium niobate (KNSBN) crystal is one of the important photorefractive ferroelectric crystal materials, not only having good photorefractive properties, but also many advantages over other photorefractive crystal materials: (ⅰ) it is easy to grow in large size, (ⅱ) neither twinning nor poling problems exist; (ⅲ) it can accommodate a wide range of solution; (ⅳ) it is easy to be doped with many kinds of dopants.展开更多
An optically active monomer containing azobenzene moieties with chiral group (s-2-methyl-butyl), 4-[2-(methacryloyloxy)ethyloxy] -4'-(s-2-methyl-1-butyloxycarbonyl) azobenzene (M1) was synthesized. Polymer (PM1) p...An optically active monomer containing azobenzene moieties with chiral group (s-2-methyl-butyl), 4-[2-(methacryloyloxy)ethyloxy] -4'-(s-2-methyl-1-butyloxycarbonyl) azobenzene (M1) was synthesized. Polymer (PM1) possessing optical phase conjugated response was obtained by homopolymerization of the optically active monomer (M1) using free radical polymerization. The polymer was very soluble in common solvents and good optical quality films could be easily fabricated by spin coating. The optical phase conjugated responses of the polymer PM1 were measured by degenerate four-wave mixing (DFWM). In comparison with polymer containing no chiral group, it was found from the preliminary measurement of photoisomeric change that optical phase conjugated response of the PM1 in the long-range order hexagonal symmetry microstructure could be easily controlled by choosing the appropriate polarization direction of the irradiating beams (514.5 nm) and the irradiating number, presumably due to the chiral group in the PM1 molecular structure. For the case of the polymer investigated here, a chiral group side chain was introduced to increase optical phase conjugated response intensity with different polarization directions of the irradiating beams, which aims originally at searching for a new photoactive material.展开更多
The phase conjugation between the deformable mirror and the wavefront sensor in the aberration correction of a terawatt Ti：sapphire laser is studied experimentally and theoretically in this paper. At varying values o...The phase conjugation between the deformable mirror and the wavefront sensor in the aberration correction of a terawatt Ti：sapphire laser is studied experimentally and theoretically in this paper. At varying values of phase- conjugation precision, we focus the corresponding beams into spots of the same size of 5.1 μm × 5.3 μm with a f/4 parabola in the 32 TW/36 fs Ti：sapphire laser system. The results show that the precision of conjugation can induce an intensity modulation but does not significantly affect the wavefront correction.展开更多
This paper gives a detailed theoretical investigation on phase conjugation induced by nearly degenerate fourwave mixing in single mode vertical-cavity surface-emitting lasers （VCSELs） with weak optical injection. Co...This paper gives a detailed theoretical investigation on phase conjugation induced by nearly degenerate fourwave mixing in single mode vertical-cavity surface-emitting lasers （VCSELs） with weak optical injection. Considering VCSELs that can work in linearly polarized or elliptically polarized states, it derives the theoretical expression of the conjugated field by small signal analysis based on the vectoral rate equations-the spin-flip model. For linearly polarized state, VCSELs show similar conjugate spectra to edge-emitting semiconductor lasers. For the elliptically polarized state, dichroism and birefringence parameters as well as the spin-flip rate can change the conjugate spectra. Especially, when frequency detuning of the probe and pump waves is between the positive and negative relaxation oscillation frequency, changes are evident. For specific values of parameters, conjugate efficiency between 20 dB to 40 dB are obtained.展开更多
This paper reports that the nonlinear refractive index of a novel organic optical storage film doped azodiphenylamine polymer is measured by using the Z-scan technique. The nonlinear refractive index up to 3.7× 1...This paper reports that the nonlinear refractive index of a novel organic optical storage film doped azodiphenylamine polymer is measured by using the Z-scan technique. The nonlinear refractive index up to 3.7× 10^-6 cm^2/W induced by thermo-optical effect is obtained. It indicates that the sample has excellent optical non- linear properties. The physical mechanism of the great nonlinear optical effect is analysed and the optical conjugate characteristic is also discussed with degenerate four-wave-mixing. The phase conjugate wave diffracted from the formative refractive index grating in the sample is acquired and its equivalent reflectivity reaches about 22%. On this basis, the reflective wave phase-conjugated mirror system was designed, and the image aberration experienced in propagation in the storage experiment is corrected by using the system.展开更多
The signal synchronization transmission of a spatiotemporal chaos network is investigated. The structure of the coupling function between connected nodes of the complex network and the value range of the linear term c...The signal synchronization transmission of a spatiotemporal chaos network is investigated. The structure of the coupling function between connected nodes of the complex network and the value range of the linear term coefficient of the separated configuration in state equation of the node are obtained through constructing an appropriate Lyapunov function. Each node of the complex network is a laser spatiotemporal chaos model in which the phase-conjugate wave and the unilateral coupled map lattice are taken as a local function and a spatially extended system, respectively. The simulation results show the effectiveness of the signal synchronization transmission principle of the network.展开更多
A novel configuration to produce bidirectional phase conjugate wave due to the self-pumping of one of two incident beams is experimentally investigated and analyzed with photorefractive KNSBN: Cu crystal. The phase co...A novel configuration to produce bidirectional phase conjugate wave due to the self-pumping of one of two incident beams is experimentally investigated and analyzed with photorefractive KNSBN: Cu crystal. The phase conjugate reflectivities and the response time are presented as functions of the ratio of input-beam intensities and the signal incident positions.展开更多
Lithium(Li)metal anodes have attracted extensive attention due to their ultrahigh theoretical capacity and low potential.However,the uneven deposition of Li near the unstable electrode/electrolyte interfaces leads to ...Lithium(Li)metal anodes have attracted extensive attention due to their ultrahigh theoretical capacity and low potential.However,the uneven deposition of Li near the unstable electrode/electrolyte interfaces leads to the growth of Li dendrites and the degradation of active electrodes.Herein,we directly fluorinate alkyne-containing conjugated microporous polymers(ACMPs)microspheres with fluorine gas(F_(2))to introduce a novel fluorinated interlayer as an interfacial stabilizer in lithium metal batteries.Using density functional theory methods,it is found that as-prepared fluorinated ACMP(FACMP)has abundant partially ionic C–F bonds.The C–F bonds with electrochemical lability yield remarkable lithiophilicity during cycling.The in situ reactions between the active C–F bonds and Li ions enable transfer of lithium fluoride microcrystals to the solid electrolyte interphase(SEI)layers,guaranteeing effective ionic distribution and smooth Li deposition.Consequently,Li metal electrodes with the fluorinated interlayers demonstrate excellent cycling performances in both half-batteries and full cells with a lithium bis(trifluoromethanesulfonyl)imide electrolyte as well as a nonfluorinated lithium bis(oxalate)borate electrolyte system.This strategy is highly significant in customizable SEI layers to stabilize electrode interfaces and ensure high utilization of Li metal anodes,especially in a nonfluorinated electrolyte.展开更多
Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of k...Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS. The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries, finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS. Numerical simulations are very helpful for understanding the complex optical phenomena.展开更多
Formamidinium lead iodide(FAPbI_(3))perovskite exhibits an impressive X-ray absorption coefficient and a large carrier mobility-lifetime product(μτ),making it as a highly promising candidate for X-ray detection appl...Formamidinium lead iodide(FAPbI_(3))perovskite exhibits an impressive X-ray absorption coefficient and a large carrier mobility-lifetime product(μτ),making it as a highly promising candidate for X-ray detection application.However,the presence of larger FA^(+)cation induces to an expansion of the Pb-I octahedral framework,which unfortunately affects both the stability and charge carrier mobility of the corresponding devices.To address this challenge,we develop a novel low-dimensional(HtrzT)PbI_(3) perovskite featuring a conjugated organic cation(1H-1,2,4-Triazole-3-thiol,HtrzT^(+))which matches well with theα-FAPbI_(3) lattices in two-dimensional plane.Benefiting from the matched lattice between(HtrzT)PbI_(3) andα-FAPbI_(3),the anchored lattice enhances the Pb-I bond strength and effectively mitigates the inherent tensile strain of theα-FAPbI_(3) crystal lattice.The X-ray detector based on(HtrzT)PbI_(3)(1.0)/FAPbI_(3) device achieves a remarkable sensitivity up to 1.83×10^(5)μC Gy_(air)^(−1) cm^(−2),along with a low detection limit of 27.6 nGy_(air) s^(−1),attributed to the release of residual stress,and the enhancement in carrier mobility-lifetime product.Furthermore,the detector exhibits outstanding stability under X-ray irradiation with tolerating doses equivalent to nearly 1.17×10^(6) chest imaging doses.展开更多
For the Shapiro-Wagner-Hradil phase detection description the canonical commutation relation between phase angleψand two-mode number-difference operator D=a^(†)a-b^(†)b is constructed.Departing from[ψ,D]=-i,the phas...For the Shapiro-Wagner-Hradil phase detection description the canonical commutation relation between phase angleψand two-mode number-difference operator D=a^(†)a-b^(†)b is constructed.Departing from[ψ,D]=-i,the phase angle Hermitian operator is derived in the newly obtained representation<ξ|,where|ξ>is the common eigenket of a+b^(†)and b+a^(†).展开更多
The technology for phase detection of liquid crystal optical device is a difficult research in current domestic and overseas. However, for the existing liquid crystal optical device, aiming at the poor anti-vibration ...The technology for phase detection of liquid crystal optical device is a difficult research in current domestic and overseas. However, for the existing liquid crystal optical device, aiming at the poor anti-vibration capability and poor versatile of phase detection, the complexity of phase retrieval algorithm, we propose a new phase measurement principle and experimental methods of liquid crystal optical device. It is a phase measurement method based on the combination of phase- shifting interferometer and phase conjugation technology. The deflection characteristics of the liquid crystal device means the device can implement phase modulation to only one direction of polarized light while is completely transparent to orthogonal polarized light. We put forward the phase shift of the orthogonal polarization phase shift interferometer method, using phase shifting interference as well as the combination of phase conjugate means to achieve its phase measurement. So we can retrieves devices modulation phase simply and efficiently combines with phase- shifting interferometer technology.展开更多
The development of new chiral stationary phases has been very important in the a ccurate analysis of drug enantiomers and their metabolites in biological samples during drug discovery and development. New chiral stati...The development of new chiral stationary phases has been very important in the a ccurate analysis of drug enantiomers and their metabolites in biological samples during drug discovery and development. New chiral stationary phases have been d eveloped using conalbumin and flavoprotein from chicken egg whites, which have b een applied to a broad range of drug enantiomers. The application and characteri zation of these two chiral columns for high-performance liquid chromatograp hy have been documented. Both specific and non-specific interactions, based on the silica gel surface and linker moiety, influenced retention and chiral separa tion of solutes. Interactions between drug enantiomers and proteins, as a pseudo chiral stationary phase, were investigated with affinity capillary electrophore sis, in order to avoid the effects of non-specific interactions. The chiral dis crimination region for ketoprofen on the flavoprotein surface was concluded to c onsist of an α-helix structure. Studies with chemically modified flavoprot ein indicated that two types of interactions at the chiral discrimination region were required for chiral separation: a π-π interaction between a tryptophan residue and the aromatic ring of ketoprofen, and an ionic interaction between th e carboxyl group of ketoprofen and an amino and carboxyl group of the protein. I n the bod y, drugs and biologically active substances having a carboxyl group have been kn own to transform various metabolites such as acyl glucuronide. The acyl adenylat e has also been noted as a chemically active intermediate of coenzyme A ligation . Both the acyl adenylate and the acyl glucuronide produced protein adducts by r eacting with nucleophilic groups such as amino groups on protein molecules. To c haracterize both active intermediates and protein adducts, analytical techniques conferring highly selective molecular recognition, such as high-performance li quid chromatography and mass spectrometry, were required.展开更多
A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a ...A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy load.The relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM structures.The 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition rate.Therefore,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved.展开更多
The optimized optical phase conjugation （OPC） configuration is proposed for the 40-Gb/s CO-OFDM system. The proposed configuration for nonlinear cancellation is systematically depicted in transmission links with lum...The optimized optical phase conjugation （OPC） configuration is proposed for the 40-Gb/s CO-OFDM system. The proposed configuration for nonlinear cancellation is systematically depicted in transmission links with lumped amplification. Numerical simulations are performed to demonstrate effectiveness. Simulation results show that mid-span spectral inversion （MSSI） can partially compensate for nonlinear distortions. Moreover, its optimized configuration can further improve system performances and increase nonlinear compensation effectiveness. Compared with MSSI, the maximal Q factor, nonlinear threshold, and transmission distance of optimized OPC configuration increase by over 1.6 dB, 2 dB, and 2 times, respectively.展开更多
A method is proposed to optimize the recording structure of the photorefractive volume grating to compensate high spatial frequency in the distorted wavefront by optical phase conjugation.Based on the coupled-wave equ...A method is proposed to optimize the recording structure of the photorefractive volume grating to compensate high spatial frequency in the distorted wavefront by optical phase conjugation.Based on the coupled-wave equation, the diffraction efficiency of the recorded grating formed by the scattered beams in different recording structures is simulated.The theoretical results show that the recorded modulations with high spatial frequency can be significantly improved in the small recording angle.In the experiment, three recording structures with the recording angles of 7.5°, 30°, and 45° are chosen to verify the compensation effect.Compared with the reconstructed image in the large recording angle of 45°, the signal to noise ratio of the image recorded at 7.5° increases to 3.2 times of that at 45°.展开更多
Optical frequency domain phase conjugation(FDPC) is based on phase conjuga-tion of spectrum of an input signal.It is equivalent to the phase conjugation and the time reversal of the temporal envelope of an input signa...Optical frequency domain phase conjugation(FDPC) is based on phase conjuga-tion of spectrum of an input signal.It is equivalent to the phase conjugation and the time reversal of the temporal envelope of an input signal.The use of FDPC to con-trol polarization signal distortion in birefringent optical fiber systems is proposed.Evolution of polarization signals in the system using midway FDPC is analyzed theoretically and simulated numerically.It is shown that the distortion of polariza-tion signals can be controlled effectively by FDPC.The impairments due to disper-sion and nonlinear effects can be suppressed simultaneously.展开更多
文摘Self-pumped phase conjugation （SPPC） is completely self-contained and requires no external mirrors, pumping beams or applied electric fields. Because of its simplicity and high reflectivity, SPPC has a host of potential applications including correcting spatial phase distortion, and optical image processing. At the present time, SPPC has been realized in BaTiO<sub>3</sub>, KNbO<sub>3</sub>, Ce-doped SBN and KNSBN single crystals. The KNSBN
基金Project supported by the National Natural Science Foundation of China
文摘Potassium sodium strontium barium niobate (KNSBN) crystal is one of the important photorefractive ferroelectric crystal materials, not only having good photorefractive properties, but also many advantages over other photorefractive crystal materials: (ⅰ) it is easy to grow in large size, (ⅱ) neither twinning nor poling problems exist; (ⅲ) it can accommodate a wide range of solution; (ⅳ) it is easy to be doped with many kinds of dopants.
基金This work was supported by National Natural Science Foundation of China (No. 59873001)Scientific Foundation for Returned Overseas Chinese Scholars, Ministry of Education.
文摘An optically active monomer containing azobenzene moieties with chiral group (s-2-methyl-butyl), 4-[2-(methacryloyloxy)ethyloxy] -4'-(s-2-methyl-1-butyloxycarbonyl) azobenzene (M1) was synthesized. Polymer (PM1) possessing optical phase conjugated response was obtained by homopolymerization of the optically active monomer (M1) using free radical polymerization. The polymer was very soluble in common solvents and good optical quality films could be easily fabricated by spin coating. The optical phase conjugated responses of the polymer PM1 were measured by degenerate four-wave mixing (DFWM). In comparison with polymer containing no chiral group, it was found from the preliminary measurement of photoisomeric change that optical phase conjugated response of the PM1 in the long-range order hexagonal symmetry microstructure could be easily controlled by choosing the appropriate polarization direction of the irradiating beams (514.5 nm) and the irradiating number, presumably due to the chiral group in the PM1 molecular structure. For the case of the polymer investigated here, a chiral group side chain was introduced to increase optical phase conjugated response intensity with different polarization directions of the irradiating beams, which aims originally at searching for a new photoactive material.
基金Project supported by the National Basic Research Program of China(Grant No.2011CB808101)the National Natural Science Foundation of China(Grant No.60921004)
文摘The phase conjugation between the deformable mirror and the wavefront sensor in the aberration correction of a terawatt Ti：sapphire laser is studied experimentally and theoretically in this paper. At varying values of phase- conjugation precision, we focus the corresponding beams into spots of the same size of 5.1 μm × 5.3 μm with a f/4 parabola in the 32 TW/36 fs Ti：sapphire laser system. The results show that the precision of conjugation can induce an intensity modulation but does not significantly affect the wavefront correction.
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No 20070613058)the Foundation for Key Program of Ministry of Education, China (Grant No 2005105148)the Doctoral Innovation Fund of Southwest Jiaotong University of China
文摘This paper gives a detailed theoretical investigation on phase conjugation induced by nearly degenerate fourwave mixing in single mode vertical-cavity surface-emitting lasers （VCSELs） with weak optical injection. Considering VCSELs that can work in linearly polarized or elliptically polarized states, it derives the theoretical expression of the conjugated field by small signal analysis based on the vectoral rate equations-the spin-flip model. For linearly polarized state, VCSELs show similar conjugate spectra to edge-emitting semiconductor lasers. For the elliptically polarized state, dichroism and birefringence parameters as well as the spin-flip rate can change the conjugate spectra. Especially, when frequency detuning of the probe and pump waves is between the positive and negative relaxation oscillation frequency, changes are evident. For specific values of parameters, conjugate efficiency between 20 dB to 40 dB are obtained.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 19834030 and 50533010）.
文摘This paper reports that the nonlinear refractive index of a novel organic optical storage film doped azodiphenylamine polymer is measured by using the Z-scan technique. The nonlinear refractive index up to 3.7× 10^-6 cm^2/W induced by thermo-optical effect is obtained. It indicates that the sample has excellent optical non- linear properties. The physical mechanism of the great nonlinear optical effect is analysed and the optical conjugate characteristic is also discussed with degenerate four-wave-mixing. The phase conjugate wave diffracted from the formative refractive index grating in the sample is acquired and its equivalent reflectivity reaches about 22%. On this basis, the reflective wave phase-conjugated mirror system was designed, and the image aberration experienced in propagation in the storage experiment is corrected by using the system.
基金Project supported by the Natural Science Foundation of Liaoning Province,China (Grant No. 20082147)
文摘The signal synchronization transmission of a spatiotemporal chaos network is investigated. The structure of the coupling function between connected nodes of the complex network and the value range of the linear term coefficient of the separated configuration in state equation of the node are obtained through constructing an appropriate Lyapunov function. Each node of the complex network is a laser spatiotemporal chaos model in which the phase-conjugate wave and the unilateral coupled map lattice are taken as a local function and a spatially extended system, respectively. The simulation results show the effectiveness of the signal synchronization transmission principle of the network.
文摘A novel configuration to produce bidirectional phase conjugate wave due to the self-pumping of one of two incident beams is experimentally investigated and analyzed with photorefractive KNSBN: Cu crystal. The phase conjugate reflectivities and the response time are presented as functions of the ratio of input-beam intensities and the signal incident positions.
基金Science Foundation for Distinguished Young Scholars in Tianjin,Grant/Award Number:19JCJQJC61700National Natural Science Foundation of China,Grant/Award Numbers:51773147,51973151,52130303National Key R&D Program of China,Grant/Award Number:2022YFB3805702。
文摘Lithium(Li)metal anodes have attracted extensive attention due to their ultrahigh theoretical capacity and low potential.However,the uneven deposition of Li near the unstable electrode/electrolyte interfaces leads to the growth of Li dendrites and the degradation of active electrodes.Herein,we directly fluorinate alkyne-containing conjugated microporous polymers(ACMPs)microspheres with fluorine gas(F_(2))to introduce a novel fluorinated interlayer as an interfacial stabilizer in lithium metal batteries.Using density functional theory methods,it is found that as-prepared fluorinated ACMP(FACMP)has abundant partially ionic C–F bonds.The C–F bonds with electrochemical lability yield remarkable lithiophilicity during cycling.The in situ reactions between the active C–F bonds and Li ions enable transfer of lithium fluoride microcrystals to the solid electrolyte interphase(SEI)layers,guaranteeing effective ionic distribution and smooth Li deposition.Consequently,Li metal electrodes with the fluorinated interlayers demonstrate excellent cycling performances in both half-batteries and full cells with a lithium bis(trifluoromethanesulfonyl)imide electrolyte as well as a nonfluorinated lithium bis(oxalate)borate electrolyte system.This strategy is highly significant in customizable SEI layers to stabilize electrode interfaces and ensure high utilization of Li metal anodes,especially in a nonfluorinated electrolyte.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10847110)
文摘Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems （SCPCSs）. As the system parameters change, different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS. The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries, finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS. Numerical simulations are very helpful for understanding the complex optical phenomena.
基金supports from the National Natural Science Foundation of China(22375220,U2001214,22471302)the Guangdong Basic and Applied Basic Research Foundation(2024B1515020101)Open Project Fund from State Key Laboratory of Optoelectronic Materials and Technologies(OEMT-2024-KF-08).
文摘Formamidinium lead iodide(FAPbI_(3))perovskite exhibits an impressive X-ray absorption coefficient and a large carrier mobility-lifetime product(μτ),making it as a highly promising candidate for X-ray detection application.However,the presence of larger FA^(+)cation induces to an expansion of the Pb-I octahedral framework,which unfortunately affects both the stability and charge carrier mobility of the corresponding devices.To address this challenge,we develop a novel low-dimensional(HtrzT)PbI_(3) perovskite featuring a conjugated organic cation(1H-1,2,4-Triazole-3-thiol,HtrzT^(+))which matches well with theα-FAPbI_(3) lattices in two-dimensional plane.Benefiting from the matched lattice between(HtrzT)PbI_(3) andα-FAPbI_(3),the anchored lattice enhances the Pb-I bond strength and effectively mitigates the inherent tensile strain of theα-FAPbI_(3) crystal lattice.The X-ray detector based on(HtrzT)PbI_(3)(1.0)/FAPbI_(3) device achieves a remarkable sensitivity up to 1.83×10^(5)μC Gy_(air)^(−1) cm^(−2),along with a low detection limit of 27.6 nGy_(air) s^(−1),attributed to the release of residual stress,and the enhancement in carrier mobility-lifetime product.Furthermore,the detector exhibits outstanding stability under X-ray irradiation with tolerating doses equivalent to nearly 1.17×10^(6) chest imaging doses.
文摘For the Shapiro-Wagner-Hradil phase detection description the canonical commutation relation between phase angleψand two-mode number-difference operator D=a^(†)a-b^(†)b is constructed.Departing from[ψ,D]=-i,the phase angle Hermitian operator is derived in the newly obtained representation<ξ|,where|ξ>is the common eigenket of a+b^(†)and b+a^(†).
文摘The technology for phase detection of liquid crystal optical device is a difficult research in current domestic and overseas. However, for the existing liquid crystal optical device, aiming at the poor anti-vibration capability and poor versatile of phase detection, the complexity of phase retrieval algorithm, we propose a new phase measurement principle and experimental methods of liquid crystal optical device. It is a phase measurement method based on the combination of phase- shifting interferometer and phase conjugation technology. The deflection characteristics of the liquid crystal device means the device can implement phase modulation to only one direction of polarized light while is completely transparent to orthogonal polarized light. We put forward the phase shift of the orthogonal polarization phase shift interferometer method, using phase shifting interference as well as the combination of phase conjugate means to achieve its phase measurement. So we can retrieves devices modulation phase simply and efficiently combines with phase- shifting interferometer technology.
文摘The development of new chiral stationary phases has been very important in the a ccurate analysis of drug enantiomers and their metabolites in biological samples during drug discovery and development. New chiral stationary phases have been d eveloped using conalbumin and flavoprotein from chicken egg whites, which have b een applied to a broad range of drug enantiomers. The application and characteri zation of these two chiral columns for high-performance liquid chromatograp hy have been documented. Both specific and non-specific interactions, based on the silica gel surface and linker moiety, influenced retention and chiral separa tion of solutes. Interactions between drug enantiomers and proteins, as a pseudo chiral stationary phase, were investigated with affinity capillary electrophore sis, in order to avoid the effects of non-specific interactions. The chiral dis crimination region for ketoprofen on the flavoprotein surface was concluded to c onsist of an α-helix structure. Studies with chemically modified flavoprot ein indicated that two types of interactions at the chiral discrimination region were required for chiral separation: a π-π interaction between a tryptophan residue and the aromatic ring of ketoprofen, and an ionic interaction between th e carboxyl group of ketoprofen and an amino and carboxyl group of the protein. I n the bod y, drugs and biologically active substances having a carboxyl group have been kn own to transform various metabolites such as acyl glucuronide. The acyl adenylat e has also been noted as a chemically active intermediate of coenzyme A ligation . Both the acyl adenylate and the acyl glucuronide produced protein adducts by r eacting with nucleophilic groups such as amino groups on protein molecules. To c haracterize both active intermediates and protein adducts, analytical techniques conferring highly selective molecular recognition, such as high-performance li quid chromatography and mass spectrometry, were required.
基金supported by the National Natural Science Foundation of China(No. 60878005)the China Postdoctoral Science Foundation(No. 20090450966)+1 种基金the Heilongjiang Postdoctoral Science Foundationthe Natural Scientific Research Innovation Foundation in Harbin Institute of Technology(No. HIT. NSRIF.2009010)
文摘A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy load.The relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM structures.The 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition rate.Therefore,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved.
基金supported in part by the National Natural Science Foundation of China (No. 60932004)the National "863" Program of China (No. 2009AA01A345)the National "973" Program of China (No.2007CB310705)
文摘The optimized optical phase conjugation （OPC） configuration is proposed for the 40-Gb/s CO-OFDM system. The proposed configuration for nonlinear cancellation is systematically depicted in transmission links with lumped amplification. Numerical simulations are performed to demonstrate effectiveness. Simulation results show that mid-span spectral inversion （MSSI） can partially compensate for nonlinear distortions. Moreover, its optimized configuration can further improve system performances and increase nonlinear compensation effectiveness. Compared with MSSI, the maximal Q factor, nonlinear threshold, and transmission distance of optimized OPC configuration increase by over 1.6 dB, 2 dB, and 2 times, respectively.
基金supported by the National Natural Science Foundation of China(No.11774364)the Shanghai Sailing Program(No.18YF1425900)
文摘A method is proposed to optimize the recording structure of the photorefractive volume grating to compensate high spatial frequency in the distorted wavefront by optical phase conjugation.Based on the coupled-wave equation, the diffraction efficiency of the recorded grating formed by the scattered beams in different recording structures is simulated.The theoretical results show that the recorded modulations with high spatial frequency can be significantly improved in the small recording angle.In the experiment, three recording structures with the recording angles of 7.5°, 30°, and 45° are chosen to verify the compensation effect.Compared with the reconstructed image in the large recording angle of 45°, the signal to noise ratio of the image recorded at 7.5° increases to 3.2 times of that at 45°.
文摘Optical frequency domain phase conjugation(FDPC) is based on phase conjuga-tion of spectrum of an input signal.It is equivalent to the phase conjugation and the time reversal of the temporal envelope of an input signal.The use of FDPC to con-trol polarization signal distortion in birefringent optical fiber systems is proposed.Evolution of polarization signals in the system using midway FDPC is analyzed theoretically and simulated numerically.It is shown that the distortion of polariza-tion signals can be controlled effectively by FDPC.The impairments due to disper-sion and nonlinear effects can be suppressed simultaneously.
