Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS reco...Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their adequacy.The technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.展开更多
This paper reports a comprehensive analysis of the origin of the electroluminescence(EL)peaks and of the thermal droop in UV-B AlGaN-based LEDs.By carrying out spectral measurements at several temperatures and current...This paper reports a comprehensive analysis of the origin of the electroluminescence(EL)peaks and of the thermal droop in UV-B AlGaN-based LEDs.By carrying out spectral measurements at several temperatures and currents,(i)we extract information on the physical origin of the various spectral bands,and(ii) we develop a novel closed-form model based on the Shockley–Read–Hall theory and on the ABC rate equation that is able to reproduce the experimental data on thermal droop caused by non-radiative recombination through deep levels.In the samples under test,the three EL bands are ascribed to the following processes:band-to-band recombination in the quantum wells(main EL peak),a parasitic intra-bandgap radiative transition in the quantum well barriers,and a second defect-related radiative process in the p-AlGaN superlattice.展开更多
Selenium(Se)element is a promising light-harvesting material for solar cells because of the large absorption coefcient and prominent photoconductivity.However,the efciency of Se solar cells has been stagnated for a lo...Selenium(Se)element is a promising light-harvesting material for solar cells because of the large absorption coefcient and prominent photoconductivity.However,the efciency of Se solar cells has been stagnated for a long time owing to the suboptimal bandgap(>1.8 eV)and the lack of a proper electron transport layer.In this work,we tune the bandgap of the absorber to the optimal value of Shockley-Queisser limit(1.36 eV)by alloying 30%Te with 70%Se.Simultaneously,ZnO electron transport layer is selected because of the proper band alignment,and the mild reaction at ZnO/Se_(0.7)Te_(0.3) interface guarantees a good-quality heterojunction.Finally,a superior efciency of 1.85%is achieved on ZnO/Se_(0.7)Te_(0.3)solar cells.展开更多
The STAR Collaboration has offered an eminent nuclear modification factor of J/ψ at high p T and midrapidity produced in Cu-Cu collisions at sNN^（1/2） = 200 GeV. Recalling a prediction, we can understand that the f...The STAR Collaboration has offered an eminent nuclear modification factor of J/ψ at high p T and midrapidity produced in Cu-Cu collisions at sNN^（1/2） = 200 GeV. Recalling a prediction, we can understand that the feature of high-pT nuclear modification factor is related to cc produced by 2 → 1 and 2 → 2 partonic processes in deconfined matter, particularly in the prethermal stage and to the recombination of c and c. The nuclear modification factor at high p T is sensitive to the earliest form of deconfined matter that does not have a temperature.展开更多
基金conducted within the state assignment of the Ministry of Science and Higher Education for universities(Project No.FZRR-2023-0009).
文摘Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−Noyce−Shockley(SNS)recombination mechanism to show the SNS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their adequacy.The technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.
基金Bundesministerium fur Bildung und Forschung(BMBF)(03ZZ0105A,03ZZ0105B)Bundesministerium fur Wirtschaft und Energie(BMWi)(03EFCBE067)Deutsche Forschungsgemeinschaft(DFG)(CRC 787)
文摘This paper reports a comprehensive analysis of the origin of the electroluminescence(EL)peaks and of the thermal droop in UV-B AlGaN-based LEDs.By carrying out spectral measurements at several temperatures and currents,(i)we extract information on the physical origin of the various spectral bands,and(ii) we develop a novel closed-form model based on the Shockley–Read–Hall theory and on the ABC rate equation that is able to reproduce the experimental data on thermal droop caused by non-radiative recombination through deep levels.In the samples under test,the three EL bands are ascribed to the following processes:band-to-band recombination in the quantum wells(main EL peak),a parasitic intra-bandgap radiative transition in the quantum well barriers,and a second defect-related radiative process in the p-AlGaN superlattice.
基金supported by the National Natural Science Foundation of China(Grant Nos.61725401,62174064,62105110,and 61904058)Natural Science Foundation of Hubei Province(No.2021CFB373)+2 种基金Fundamental Research Funds for the Central Universities(No.2021XXJS028)National Key R&D Program of China(No.2021YFA0715502)support of the project funded by China Postdoctoral Science Foundation(Nos.2020M680101 and 2021T140233).
文摘Selenium(Se)element is a promising light-harvesting material for solar cells because of the large absorption coefcient and prominent photoconductivity.However,the efciency of Se solar cells has been stagnated for a long time owing to the suboptimal bandgap(>1.8 eV)and the lack of a proper electron transport layer.In this work,we tune the bandgap of the absorber to the optimal value of Shockley-Queisser limit(1.36 eV)by alloying 30%Te with 70%Se.Simultaneously,ZnO electron transport layer is selected because of the proper band alignment,and the mild reaction at ZnO/Se_(0.7)Te_(0.3) interface guarantees a good-quality heterojunction.Finally,a superior efciency of 1.85%is achieved on ZnO/Se_(0.7)Te_(0.3)solar cells.
基金Supported by National Natural Science Foundation of China (10675079)
文摘The STAR Collaboration has offered an eminent nuclear modification factor of J/ψ at high p T and midrapidity produced in Cu-Cu collisions at sNN^（1/2） = 200 GeV. Recalling a prediction, we can understand that the feature of high-pT nuclear modification factor is related to cc produced by 2 → 1 and 2 → 2 partonic processes in deconfined matter, particularly in the prethermal stage and to the recombination of c and c. The nuclear modification factor at high p T is sensitive to the earliest form of deconfined matter that does not have a temperature.
