Considering two beams propagate in semiconductor crystal, this paper discusses the polarization dependence of pump beam-induced intensity attenuation of probe beam due to two-photon absorption （TPA）. Numerical calcu...Considering two beams propagate in semiconductor crystal, this paper discusses the polarization dependence of pump beam-induced intensity attenuation of probe beam due to two-photon absorption （TPA）. Numerical calculation and experimental measurement demonstrate that TPA coefficient is polarization dependent. For homogeneous materials, probe beam attenuation arises from the imaginary part of diagonal and off-diagonal components of third-order nonlinear susceptibilities.展开更多
Small-molecule organic semiconductor crystals(SMOSCs) combine broadband light absorption(ultraviolet–visible–near infrared) with long exciton diffusion length and high charge carrier mobility. Therefore, they are pr...Small-molecule organic semiconductor crystals(SMOSCs) combine broadband light absorption(ultraviolet–visible–near infrared) with long exciton diffusion length and high charge carrier mobility. Therefore, they are promising candidates for realizing high-performance photodetectors. Here, after a brief resume of photodetector performance parameters and operation mechanisms, we review the recent advancements in application of SMOSCs as photodetectors, including photoconductors, phototransistors, and photodiodes. More importantly, the SMOSC-based photodetectors are further categorized according to their detection regions that cover a wide range from ultraviolet to near infrared. Finally, challenges and outlooks of SMOSC-based photodetectors are provided.展开更多
Owing to enhanced charge transport efficiency arising from the ultrathin nature,two-dimensional(2D)organic semiconductor single crystals(OSSCs)are emerging as a fascinating platform for high-performance organic field-...Owing to enhanced charge transport efficiency arising from the ultrathin nature,two-dimensional(2D)organic semiconductor single crystals(OSSCs)are emerging as a fascinating platform for high-performance organic field-effect transistors(OFETs).However,ucoffee-ring"effect induced by an evaporation-induced convective flow near the contact line hinders the large-area growth of 2D OSSCs through a solution process.Here,we develop a new strategy of suppressing the"coffee-ring"effect by using an organic semiconductor:polymer blend solution.With the high-viscosity polymer in the organic solution,the evaporation-induced flow is remarkably weakened,ensuring the uniform molecule spreading for the 2D growth of the OSSCs.As an example,wafer-scale growth of crystalline film consisting of few-layered 2,7-didecylbenzothienobenzothiophene(C10-BTBT)crystals was successfully accomplished via blade coating.OFETs based on the crystalline film exhibited a maximum hole mobility up to 12.6 cm^2·V^-1·s^-1,along with an average hole mobility as high as 8.2 cm^2·V^-1·s^-1.Our work provides a promising strategy for the large-area growth of 2D OSSCs toward high-performance organic electronics.展开更多
The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） i...The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） is deduced based on the transfer matrix method, and the electromagnetic plane wave numerical simulation of this 1DDPC is performed by using the finite element method. The calculated and simulated results have confirmed that the filtering transmittance of this 1DDPC in symmetric structure of air/（Si/SiO_2）~N/GaAs/（SiO_2/Si）~N/air is far higher than in asymmetric structure of air/（Si/SiO_2）~N/GaAs/（Si/SiO_2）~N/air, where the filtering frequency can be tuned by the external pressure. It can provide a feasible route to design the external pressure-controlled THz filter based on 1DPC with a defective semiconductor.展开更多
We describe theoretically the grounded method of measuring the conductivity of anisotropic layered semiconductor materials. The suggested method implies the use of a four-probe testing device with a linear arrangement...We describe theoretically the grounded method of measuring the conductivity of anisotropic layered semiconductor materials. The suggested method implies the use of a four-probe testing device with a linear arrangement of probes. The final expressions for identifying the electrical conductivity are presented in the form of a series of analytic functions. The suggested method is experimentally verified, and practical recommendations of how to apply it are also provided.展开更多
Photonic crystals(PCs) have attracted much considerable research attention in the past two decades. They are artificially fabricated periodic dielectric structures. The periodic dielectric structures have photonic ban...Photonic crystals(PCs) have attracted much considerable research attention in the past two decades. They are artificially fabricated periodic dielectric structures. The periodic dielectric structures have photonic band gap(PBG) and are referred to as photonic band gap materials. This paper mainly introduces one-dimensional (1-D) and 2D PCs applied in the semiconductor lasers.展开更多
Two‐dimensional organic semiconductor single crystals(2D OSSCs)represent the promising candidates for the construction of high‐performance electronic and optoelectronic devices due to their ultrathin thicknesses,fre...Two‐dimensional organic semiconductor single crystals(2D OSSCs)represent the promising candidates for the construction of high‐performance electronic and optoelectronic devices due to their ultrathin thicknesses,free of grain boundaries,and long‐range ordered molecular structures.In recent years,substantial efforts have been devoted to the fabrication of the large‐sized and layer‐controlled 2D OSSCs at the liquid‐liquid interface.This unique interface could act as the molecular flat and defect‐free substrate for regulating the nucleation and growth processes and enabling the formation of large‐sized ultrathin 2D OSSCs.Therefore,this review focuses on the liquid-liquid interface‐assisted growth methods for the controllable preparation of 2D OSSCs,with a particular emphasis on the advantages and limitations of the corresponding methods.Furthermore,the typical methods employed to control the crystal sizes,morphologies,structures,and orientations of 2D OSSCs at the liquid-liquid interface are discussed in detail.Then,the recent progresses on the 2D OSSCs‐based optoelectronic devices,such as organic field‐effect transistors,ambipolar transistors,and phototransistors are highlighted.Finally,the key challenges and further outlook are proposed in order to promote the future development of the 2D OSSCs in the field of the next‐generation organic optoelectronic devices.展开更多
Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-ty...Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-type conductivity, with a carrier concentration of approximately 10^14cm^-3, a mobility of approximately 300 cm^2·V·s^-1, and a resistivity of approximately 10^2 Ω·cm. A simple and effective method was proposed for chemical surface texturization of ZnTe using an HF：H2O2：H2O etchant. Textures with the sizes of approximately 1μm were produced on {100}, {110}, and { 111}zn surfaces after etching. The etchant is also very promising in crystal characterization because of its strong anisotropic character and Te-phase selectivity.展开更多
This paper demonstrates experimentally and numerically that a significant modification of spontaneous emission rate can be achieved near the surface of a three-dimensional photonic crystal. In experiments, semiconduct...This paper demonstrates experimentally and numerically that a significant modification of spontaneous emission rate can be achieved near the surface of a three-dimensional photonic crystal. In experiments, semiconductor coreshell quantum dots are intentionally confined in a thin polymer film on which a three-dimensional colloidal photonic crystal is fabricated. The spontaneous emission rate of quantum dots is characterised by conventional and time-resolved photoluminescence （PL） measurements. The modification of the spontaneous emission rate, which is reflected in the change of spectral shape and PL lifetime, is clearly observed. While an obvious increase in the PL lifetime is found at most wavelengths in the band gap, a significant reduction in the PL lifetime by one order of magnitude is observed at the short-wavelength band edge. Numerical simulation reveals a periodic modulation of spontaneous emission rate with decreasing modulation strength when an emitter is moved away from the surface of the photonic crystal. It is supported by the fact that the modification of spontaneous emission rate is not pronounced for quantum dots distributed in a thick polymer film where both enhancement and suppression are present simultaneously. This finding provides a simple and effective way for improving the performance of light emitting devices.展开更多
文摘Considering two beams propagate in semiconductor crystal, this paper discusses the polarization dependence of pump beam-induced intensity attenuation of probe beam due to two-photon absorption （TPA）. Numerical calculation and experimental measurement demonstrate that TPA coefficient is polarization dependent. For homogeneous materials, probe beam attenuation arises from the imaginary part of diagonal and off-diagonal components of third-order nonlinear susceptibilities.
基金supported by the National Natural Science Foundation of China(Grant Nos.51672180,51622306,and 21673151)Collaborative Innovation Center of Suzhou Nano Science&Technology+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the 111 Project,Joint International Research Laboratory of Carbon-Based Functional Materials and Devices
文摘Small-molecule organic semiconductor crystals(SMOSCs) combine broadband light absorption(ultraviolet–visible–near infrared) with long exciton diffusion length and high charge carrier mobility. Therefore, they are promising candidates for realizing high-performance photodetectors. Here, after a brief resume of photodetector performance parameters and operation mechanisms, we review the recent advancements in application of SMOSCs as photodetectors, including photoconductors, phototransistors, and photodiodes. More importantly, the SMOSC-based photodetectors are further categorized according to their detection regions that cover a wide range from ultraviolet to near infrared. Finally, challenges and outlooks of SMOSC-based photodetectors are provided.
基金This work was supported by the National Natural Science Foundation of China(Nos.51973147,61904117,51821002 and 51672180)the Natural Science Foundation of Jiangsu Province of China(No.BK20180845)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),the 111 Project,Joint International Research Laboratory of Carbon-Based Functional Materials and DevicesThe authors thank the Collaborative Innovation Center of Suzhou Nano Science and Technology(Nano-CIC),Soochow University and Beamline BLI4B1(Shanghai Synchrotron Radiation Facility)for providing beam time.
文摘Owing to enhanced charge transport efficiency arising from the ultrathin nature,two-dimensional(2D)organic semiconductor single crystals(OSSCs)are emerging as a fascinating platform for high-performance organic field-effect transistors(OFETs).However,ucoffee-ring"effect induced by an evaporation-induced convective flow near the contact line hinders the large-area growth of 2D OSSCs through a solution process.Here,we develop a new strategy of suppressing the"coffee-ring"effect by using an organic semiconductor:polymer blend solution.With the high-viscosity polymer in the organic solution,the evaporation-induced flow is remarkably weakened,ensuring the uniform molecule spreading for the 2D growth of the OSSCs.As an example,wafer-scale growth of crystalline film consisting of few-layered 2,7-didecylbenzothienobenzothiophene(C10-BTBT)crystals was successfully accomplished via blade coating.OFETs based on the crystalline film exhibited a maximum hole mobility up to 12.6 cm^2·V^-1·s^-1,along with an average hole mobility as high as 8.2 cm^2·V^-1·s^-1.Our work provides a promising strategy for the large-area growth of 2D OSSCs toward high-performance organic electronics.
基金partially supported by National Natural Science Foundation of China(Grant Nos.11174147,11175152 and11704326)the Funding of Jiangsu Innovation Program for Graduate Education(Grant No.KYLX15_0316)the Fundamental Research Funds for the Central Universities
文摘The tunable terahertz（THz） filter has been designed and studied, which is composed of 1D photonic crystal（PC） containing a defect layer of semiconductor Ga As. The analytical solution of 1D defective PC（1DDPC） is deduced based on the transfer matrix method, and the electromagnetic plane wave numerical simulation of this 1DDPC is performed by using the finite element method. The calculated and simulated results have confirmed that the filtering transmittance of this 1DDPC in symmetric structure of air/（Si/SiO_2）~N/GaAs/（SiO_2/Si）~N/air is far higher than in asymmetric structure of air/（Si/SiO_2）~N/GaAs/（Si/SiO_2）~N/air, where the filtering frequency can be tuned by the external pressure. It can provide a feasible route to design the external pressure-controlled THz filter based on 1DPC with a defective semiconductor.
基金Supported by the Ministry of Education and Science of the Russian Federation under Grant No 2271
文摘We describe theoretically the grounded method of measuring the conductivity of anisotropic layered semiconductor materials. The suggested method implies the use of a four-probe testing device with a linear arrangement of probes. The final expressions for identifying the electrical conductivity are presented in the form of a series of analytic functions. The suggested method is experimentally verified, and practical recommendations of how to apply it are also provided.
文摘Photonic crystals(PCs) have attracted much considerable research attention in the past two decades. They are artificially fabricated periodic dielectric structures. The periodic dielectric structures have photonic band gap(PBG) and are referred to as photonic band gap materials. This paper mainly introduces one-dimensional (1-D) and 2D PCs applied in the semiconductor lasers.
基金National Natural Science Foundation of China,Grant/Award Numbers:51821002,52173178,52225303Science and Technology Development Fund of the Macao Special Administrative Region,Grant/Award Number:0145/2022/A3+1 种基金Suzhou Gusu innovation and entrepreneurship leading talent project,Grant/Award Number:ZXL2023342Jiangsu Provincial Department of Science and Technology leading technology basic research major project,Grant/Award Number:BK20232041。
文摘Two‐dimensional organic semiconductor single crystals(2D OSSCs)represent the promising candidates for the construction of high‐performance electronic and optoelectronic devices due to their ultrathin thicknesses,free of grain boundaries,and long‐range ordered molecular structures.In recent years,substantial efforts have been devoted to the fabrication of the large‐sized and layer‐controlled 2D OSSCs at the liquid‐liquid interface.This unique interface could act as the molecular flat and defect‐free substrate for regulating the nucleation and growth processes and enabling the formation of large‐sized ultrathin 2D OSSCs.Therefore,this review focuses on the liquid-liquid interface‐assisted growth methods for the controllable preparation of 2D OSSCs,with a particular emphasis on the advantages and limitations of the corresponding methods.Furthermore,the typical methods employed to control the crystal sizes,morphologies,structures,and orientations of 2D OSSCs at the liquid-liquid interface are discussed in detail.Then,the recent progresses on the 2D OSSCs‐based optoelectronic devices,such as organic field‐effect transistors,ambipolar transistors,and phototransistors are highlighted.Finally,the key challenges and further outlook are proposed in order to promote the future development of the 2D OSSCs in the field of the next‐generation organic optoelectronic devices.
基金financially supported by the National Basic Research Program of China (No. 2011CB610406)the National Natural Science Foundation of China (No. 51372205)+3 种基金supported by the 111 Project of China (No. B08040)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20116102120014)the Northwestern Polytechnical University Foundation for Fundamental Researchthe Research Fund of the State Key Laboratory of Solidification Processing (NWPU)
文摘Using tellurium as a solvent, we grew ZnTe ingots of 30 mm in diameter and 70 mm in length by a temperature gradient solution growth method. Hall tests conducted at 300 K indicated that the as-grown ZnTe exhibits p-type conductivity, with a carrier concentration of approximately 10^14cm^-3, a mobility of approximately 300 cm^2·V·s^-1, and a resistivity of approximately 10^2 Ω·cm. A simple and effective method was proposed for chemical surface texturization of ZnTe using an HF：H2O2：H2O etchant. Textures with the sizes of approximately 1μm were produced on {100}, {110}, and { 111}zn surfaces after etching. The etchant is also very promising in crystal characterization because of its strong anisotropic character and Te-phase selectivity.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10974060 and 10774050)the Program for Innovative Research Team of the Higher Education in Guangdong,China (Grant No. 06CXTD005)
文摘This paper demonstrates experimentally and numerically that a significant modification of spontaneous emission rate can be achieved near the surface of a three-dimensional photonic crystal. In experiments, semiconductor coreshell quantum dots are intentionally confined in a thin polymer film on which a three-dimensional colloidal photonic crystal is fabricated. The spontaneous emission rate of quantum dots is characterised by conventional and time-resolved photoluminescence （PL） measurements. The modification of the spontaneous emission rate, which is reflected in the change of spectral shape and PL lifetime, is clearly observed. While an obvious increase in the PL lifetime is found at most wavelengths in the band gap, a significant reduction in the PL lifetime by one order of magnitude is observed at the short-wavelength band edge. Numerical simulation reveals a periodic modulation of spontaneous emission rate with decreasing modulation strength when an emitter is moved away from the surface of the photonic crystal. It is supported by the fact that the modification of spontaneous emission rate is not pronounced for quantum dots distributed in a thick polymer film where both enhancement and suppression are present simultaneously. This finding provides a simple and effective way for improving the performance of light emitting devices.
