[1] [1] ZOU W Q,VISSER C,MADURO J A,et al. Broadband dye-sensitized upconversion of near-infrared light[J]. Nature Photonics, 2012,6(8):560-564. doi:10.1038/nphoton.2012.158.

[2] [2] ZHAO J B, JIN D Y, SCHARTNER E P, et al. Single-nanocrystal sensitivity achieved by enhanced upconversion luminescence [J]. Nature Nanotechnology, 2013,8(10):729-734. doi:10.1038/nnano.2013.171.

[3] [3] WU D M,GARCA-ETXARRI A,SALLEO A,et al. Plasmon-enhanced upconversion[J]. The Journal of Physical Chemistry Letters, 2014,5(22):4020-4031. doi:10.1021/jz5019042.

[4] [4] LIU Qian,FENG Wei,YANG Tianshe,et al. Upconversion luminescence imaging of cells and small animals[J]. Nature Protocols, 2013,8(10):2033-2044. doi:10.1038/nprot.2013.114.

[5] [5] YANG Yining, ZHANG Yong, SHEN Wei, et al. Semiconductor infrared up-conversion devices[J]. Progress in Quantum Electronics, 2011,35(4):77-108. doi:10.1016/j.pquantelec.2011.05.001.

[6] [6] XIE Xiaoji,LIU Xiaogang. Upconversion goes broadband[J]. Nature Materials, 2012,11(10):842-843. doi:10.1038/nmat3426.

[7] [7] VAN SARK W G,DE-WILD J,RATH J K,et al. Upconversion in solar cells[J]. Nanoscale Research Letters, 2013,8(1):81. doi: 10.1186/1556-276X-8-81.

[8] [8] PFEIFFER T,KUTAS M,HAASE B,et al. Terahertz detection by upconversion to the near-infrared using picosecond pulses[J]. Optics Express, 2020,28(20):29419-29429. doi:10.1364/OE.397839.

[9] [9] KHAN M J, CHEN J C, KAUSHIK S. Optical detection of terahertz using nonlinear parametric upconversion[J]. Optics Letters, 2008,33(23):2725-2727. doi:10.1364/OL.33.002725.

[10] [10] BARH A, PEDERSEN C, TIDEMAND-LICHTENBERG P. Ultra-broadband mid-wave-IR upconversion detection[J]. Optics Letters, 2017,42(8):1504. doi:10.1364/OL.42.001504.

[11] [11] ALBOTA M A, WONG F N C. Efficient single-photon counting at 155 m by means of frequency upconversion[J]. Optics Letters, 2004,29(13):1449. doi:10.1364/OL.29.001449.

[12] [12] AHARON A,ROZBAN D,KLEIN A,et al. Detection and upconversion of three-dimensional MMW/THz images to the visible[J]. Photonics Research, 2016,4(6):306. doi:10.1364/PRJ.4.000306.

[13] [13] KOZINA M, FECHNER M, MARSIK P, et al. Terahertz-driven phonon upconversion in SrTiO3[J]. Nature Physics, 2019, 15(4): 387-392. doi:10.1038/s41567-018-0408-1.

[14] [14] BAI Peng, ZHANG Yueheng, SHEN Wenzheng. Infrared single photon detector based on optical up-converter at 1 550 nm[J]. Scientific Reports, 2017,7(1):15341. doi:10.1038/s41598-017-15613-0.

[15] [15] DOWNES L A,MACKELLAR A R,WHITING D J,et al. Full-field terahertz imaging at kilohertz frame rates using atomic vapor[J]. Physical Review X, 2020,10(1):011027. doi:10.1103/PhysRevX.10.011027.

[16] [16] BAN D,HAN S,LU Z H,et al. Near-infrared to visible light optical upconversion by direct tandem integration of organic light-emitting diode and inorganic photodetector[J]. Applied Physics Letters, 2007,90(9):093108. doi:10.1063/1.2710003.

[17] [17] BAN D,LUO H M,LIU H C,et al. Midinfrared optical upconverter[J]. Applied Physics Letters, 2005,86(20):201103. doi:10.1063/1.1921330.

[18] [18] FU Zhili,GU Lin,GUO Xiaogang,et al. Frequency up-conversion photon-type terahertz imager[J]. Scientific Reports, 2016,6(1): 25383. doi:10.1038/srep25383.

[19] [19] ALLARD L B,LIU H C,BUCHANAN M,et al. Pixelless infrared imaging utilizing a p-type quantum well infrared photodetector integrated with a light emitting diode[J]. Applied Physics Letters, 1997,70(21):2784-2786. doi:10.1063/1.119058.

[20] [20] DUPONT E,BYLOOS M,GAO M,et al. Pixelless thermal imaging with integrated quantum-well infrared photodetector and light-emitting diode[J]. IEEE Photonics Technology Letters, 2002,14(2):182-184. doi:10.1109/68.980504.

[21] [21] LIU H C, ALLARD L B, BUCHANAN M, et al. Pixelless infrared imaging device[J]. Electronics Letters, 1997, 33(5): 379. doi: 10.1049/el:19970242.

[22] [22] DUPONT E, BYLOOS M, OOGARAH T, et al. Optimization of quantum-well infrared detectors integrated with light-emitting diodes[J]. Infrared Physics & Technology, 2005,47(1/2):132-143. doi:10.1016/j.infrared.2005.02.018.

[23] [23] SCHNEIDER H,LIU H C. Quantum well infrared photodetectors[M]. Berlin: Springer, 2006. doi:10.1007/978-3-540-36324-8.

[24] [24] BAI Peng, ZHANG Yueheng, WANG Tianmeng, et al. Broadband THz to NIR up-converter for photon-type THz imaging[J]. Nature Communications, 2019,10(1):3513. doi:10.1038/s41467-019-11465-6.

[25] [25] BAI Peng,ZHANG Yuhua,GUO Xiaogang,et al. Realization of the high-performance THz GaAs homojunction detector below the frequency of reststrahlen band[J]. Applied Physics Letters, 2018,113(24):241102. doi:10.1063/1.5061696.

[26] [26] BAI Peng,LI Xiaohong,YANG Ning,et al. Broadband and photovoltaic THz/IR response in the GaAs-based ratchet photodetector[J]. Science Advances, 2022,8(21):eabn2031. doi:10.1126/sciadv.abn2031.

[27] [27] LAO Y F, PERERA A G U, LI L H, et al. Tunable hot-carrier photodetection beyond the bandgap spectral limit[J]. Nature Photonics, 2014,8(5):412-418. doi:10.1038/nphoton.2014.80.

[28] [28] KARPOV S. ABC-model for interpretation of internal quantum efficiency and its droop in III-nitride LEDs: a review[J]. Optical and Quantum Electronics, 2015,47(6):1293-1303. doi:10.1007/s11082-014-0042-9.

[29] [29] PIPREK J. Efficiency droop in nitride-based light-emitting diodes[J]. Physica Status Solidi(a), 2010, 207(10): 2217-2225. doi: 10.1002/pssa.201026149.

[30] [30] RYU H Y, KIM H S, SHIM J I. Rate equation analysis of efficiency droop in InGaN light-emitting diodes[J]. Applied Physics Letters, 2009,95(8):081114. doi:10.1063/1.3216578.

[31] [31] LI Xiaohong,PENG Bai,HUANG Siheng,et al. Bi-functional high-speed and ultrabroad bandwidth detector[J]. ACS Photonics, 2023,10(8):2816-2824. doi:10.1021/acsphotonics.3c00513.

[32] [32] PENG Bai, ZHANG Yueheng, WANG Tianmeng, et al. Cryogenic characteristics of GaAs-based near-infrared light emitting diodes[J]. Semiconductor Science and Technology, 2020,35(3):035021-1-10. doi:10.1088/1361-6641/ab6dbf.