In this study, the efficiency droop of an InGaN light-emitting diode (LED) is reduced slgnlncanUy oy using a p-AlGaN/GaN superlattice last quantum barrier. The reduction in efficiency droop is mainly caused by the d...In this study, the efficiency droop of an InGaN light-emitting diode (LED) is reduced slgnlncanUy oy using a p-AlGaN/GaN superlattice last quantum barrier. The reduction in efficiency droop is mainly caused by the decrease of electron current leakage and the increase of hole injection efficiency, which is revealed by investigating the light currents, internal quantum efficiencies, energy band diagrams, carrier concentrations, carrier current densities, and radiative recombination efficiencies of three LED structures with the advanced physical model of semiconductor device (APSYS).展开更多
This paper reviews the recent progress in the synthesis of near-infrared(NIR) lead chalcogenide(PbX;PbX = PbS,PbSe, PbTe) quantum dots(QDs) and their applications in NIR QDs based light emitting diodes(NIR-QLEDs). It ...This paper reviews the recent progress in the synthesis of near-infrared(NIR) lead chalcogenide(PbX;PbX = PbS,PbSe, PbTe) quantum dots(QDs) and their applications in NIR QDs based light emitting diodes(NIR-QLEDs). It summarizes the strategies of how to synthesize high efficiency PbX QDs and how to realize high performance Pb X based NIR-QLEDs.展开更多
Colloidal Pb Se nanocrystals(NCs)have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges.However,the fast degra...Colloidal Pb Se nanocrystals(NCs)have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges.However,the fast degradation of colloidal Pb Se NCs in ambient conditions hampers their widespread applications in infrared optoelectronics.It is well-known that the inorganic thick-shell over core improves the stability of NCs.Here,we present the synthesis of Pb Se/Pb S core/shell NCs showing wide spectral tunability,in which the molar ratio of lead(Pb)and sulfur(S)precursors,and the concentration of sulfur and Pb Se NCs in solvent have a significant effect on the efficient Pb S shell growth.The infrared light-emitting diodes(IR-LEDs)fabricated with the Pb Se/Pb S core/shell NCs exhibit an external quantum efficiency(EQE)of 1.3%at 1280 nm.The ligand exchange to optimize the distance between NCs and chloride treatment are important processes for achieving high performance on Pb Se/Pb S NC-LEDs.Our results provide evidence for the promising potential of Pb Se/Pb S NCs over the wide range of infrared optoelectronic applications.展开更多
During the last two decades, III-nitride-based quantum dots(QDs) have attracted great attentions for optoelectronic applications due to their unique electronic properties. In this paper, we first present an overview o...During the last two decades, III-nitride-based quantum dots(QDs) have attracted great attentions for optoelectronic applications due to their unique electronic properties. In this paper, we first present an overview on the techniques of fabrication for III-nitride-based QDs. Then various optoelectronic devices such as QD lasers, QD light-emitting diodes(LEDs), QD infrared photodetectors(QDIPs) and QD intermediate band(QDIB) solar cells(SCs) are discussed. Finally, we focus on the future research directions and how the challenges can be overcome.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61176043)the Special Funds for Provincial Strategic and Emerging Industries Projects of Guangdong Province,China(Grant Nos.2010A081002005,2011A081301003,and 2012A080304016)+2 种基金the First Phase of Construction of Guangdong Research Institute of Semiconductor Lighting Industrial Technology,China(Grant No.2010A081001001)the High Efficiency LED Epitaxy and Chip Structure and Key Technology for Industrialization,China(Grant No.2012A080302002)the Youth Funding of South China Normal University(Grant No.2012KJ018)
文摘In this study, the efficiency droop of an InGaN light-emitting diode (LED) is reduced slgnlncanUy oy using a p-AlGaN/GaN superlattice last quantum barrier. The reduction in efficiency droop is mainly caused by the decrease of electron current leakage and the increase of hole injection efficiency, which is revealed by investigating the light currents, internal quantum efficiencies, energy band diagrams, carrier concentrations, carrier current densities, and radiative recombination efficiencies of three LED structures with the advanced physical model of semiconductor device (APSYS).
基金Project supported by the National Key Research and Development Program,China(Grant Nos.2016YFB0401702 and 2017YFE0120400)the National Natural Science Foundation of China(Grant Nos.61875082 and 61405089)+6 种基金the Guangdong University Key Laboratory for Advanced Quantum Dot Displays and Lighting,China(Grant No.2017KSYS007)the Natural Science Foundation of Guangdong,China(Grant No.2017B030306010)the Guangdong Province’s 2018–2019 Key R&D Program:Environmentally Friendly Quantum Dots Luminescent Materials,China(Grant No.2019B010924001)the Shenzhen Innovation Project,China(Grant Nos.JCYJ20160301113356947 and JSGG20170823160757004)the Shenzhen Peacock Team Project,China(Grant No.KQTD2016030111203005)the Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting,China(Grant No.ZDSYS201707281632549)the Tianjin New Materials Science and Technology Key Project,China(Grant No.16ZXCLGX00040)
文摘This paper reviews the recent progress in the synthesis of near-infrared(NIR) lead chalcogenide(PbX;PbX = PbS,PbSe, PbTe) quantum dots(QDs) and their applications in NIR QDs based light emitting diodes(NIR-QLEDs). It summarizes the strategies of how to synthesize high efficiency PbX QDs and how to realize high performance Pb X based NIR-QLEDs.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0401702)the National Natural Science Foundation of China(Grant Nos.61674074 and 61405089)+6 种基金Development and Reform Commission of Shenzhen Project,China(Grant No.[2017]1395)Shenzhen Peacock Team Project,China(Grant No.KQTD2016030111203005)Shenzhen Key Laboratory for Advanced Quantum Dot Displays and Lighting,China(Grant No.ZDSYS201707281632549)Guangdong Province’s Key R&D Program:Micro-LED Display and Ultra-high Brightness Micro-display Technology,China(Grant No.2019B010925001)Guangdong University Key Laboratory for Advanced Quantum Dot Displays and Lighting,China(Grant No.2017KSYS007)Distinguished Young Scholar of National Natural Science Foundation of Guangdong,China(Grant No.2017B030306010)the start-up fund from Southern University of Science and Technology,Shenzhen,China
文摘Colloidal Pb Se nanocrystals(NCs)have gained considerable attention due to their efficient carrier multiplication and emissions across near-infrared and short-wavelength infrared spectral ranges.However,the fast degradation of colloidal Pb Se NCs in ambient conditions hampers their widespread applications in infrared optoelectronics.It is well-known that the inorganic thick-shell over core improves the stability of NCs.Here,we present the synthesis of Pb Se/Pb S core/shell NCs showing wide spectral tunability,in which the molar ratio of lead(Pb)and sulfur(S)precursors,and the concentration of sulfur and Pb Se NCs in solvent have a significant effect on the efficient Pb S shell growth.The infrared light-emitting diodes(IR-LEDs)fabricated with the Pb Se/Pb S core/shell NCs exhibit an external quantum efficiency(EQE)of 1.3%at 1280 nm.The ligand exchange to optimize the distance between NCs and chloride treatment are important processes for achieving high performance on Pb Se/Pb S NC-LEDs.Our results provide evidence for the promising potential of Pb Se/Pb S NCs over the wide range of infrared optoelectronic applications.
文摘During the last two decades, III-nitride-based quantum dots(QDs) have attracted great attentions for optoelectronic applications due to their unique electronic properties. In this paper, we first present an overview on the techniques of fabrication for III-nitride-based QDs. Then various optoelectronic devices such as QD lasers, QD light-emitting diodes(LEDs), QD infrared photodetectors(QDIPs) and QD intermediate band(QDIB) solar cells(SCs) are discussed. Finally, we focus on the future research directions and how the challenges can be overcome.