Zhang Kai, Li Haozhe, Mu Haoran, Li Yun, Wang Pu, Wang Yu, Chen Tongsheng, Yuan Jian, Chen Weiqiang, Yu Wenzhi, Zhang Guangyu, Bao Qiaoliang, Lin Shenghuang
Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science & Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou, 510631, China.
Adv Mater. 2024 Sep;36(38):e2405233. doi: 10.1002/adma.202405233. Epub 2024 Aug 1.
Light-induced ferroelectric polarization in 2D layered ferroelectric materials holds promise in photodetectors with multilevel current and reconfigurable capabilities. However, translating this potential into practical applications for high-density optoelectronic information storage remains challenging. In this work, an α-InSe/Te heterojunction design that demonstrates spatially resolved, multilevel, nonvolatile photoresponsivity is presented. Using photocurrent mapping, the spatially localized light-induced poling state (LIPS) is visualized in the junction region. This localized ferroelectric polarization induced by illumination enables the heterojunction to exhibit enhanced photoresponsivity. Unlike previous reports that observe multilevel polarization enhancement in electrical resistance, the device shows nonvolatile photoresponsivity enhancement under illumination. After polarization saturation, the photocurrent increases up to 1000 times, from 10 to 10 A under the irradiation of a 520 nm laser with a power of 1.69 nW, compared to the initial state in a self-driven mode. The photodetector exhibits high detectivity of 4.6×10 Jones, with a rise time of 27 µs and a fall time of 28 µs. Furthermore, the device's localized poling characteristics and multilevel photoresponse enable spatially multiplexed optical information storage. These results advance the understanding of LIPS in 2D ferroelectric materials, paving the way for optoelectronic information storage technologies.
二维层状铁电材料中的光致铁电极化在具有多级电流和可重构能力的光电探测器中具有应用前景。然而，将这种潜力转化为高密度光电信息存储的实际应用仍然具有挑战性。在这项工作中，提出了一种α-InSe/Te异质结设计，该设计展示了空间分辨的、多级的、非易失性光响应。利用光电流映射，在结区可视化了空间局部化的光致极化状态（LIPS）。光照诱导的这种局部铁电极化使异质结表现出增强的光响应。与之前观察到电阻中多级极化增强的报道不同，该器件在光照下表现出非易失性光响应增强。在极化饱和后，与自驱动模式下的初始状态相比，在功率为1.69 nW的520 nm激光照射下，光电流从10 μA增加到1000 μA，增长了1000倍。该光电探测器具有4.6×10¹² Jones的高探测率，上升时间为27 μs，下降时间为28 μs。此外，该器件的局部极化特性和多级光响应实现了空间复用光学信息存储。这些结果推进了对二维铁电材料中LIPS的理解，为光电信息存储技术铺平了道路。
