Chen Yan, Wang Xudong, Huang Le, Wang Xiaoting, Jiang Wei, Wang Zhen, Wang Peng, Wu Binmin, Lin Tie, Shen Hong, Wei Zhongming, Hu Weida, Meng Xiangjian, Chu Junhao, Wang Jianlu
State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai, China.
School of Physics and Electronic Science, East China Normal University, Shanghai, China.
Nat Commun. 2021 Jun 29;12(1):4030. doi: 10.1038/s41467-021-24296-1.
Van der Waals integration with abundant two-dimensional materials provides a broad basis for assembling functional devices. In a specific van der Waals heterojunction, the band alignment engineering is crucial and feasible to realize high performance and multifunctionality. Here, we design a ferroelectric-tuned van der Waals heterojunction device structure by integrating a GeSe/MoS VHJ and poly (vinylidene fluoride-trifluoroethylene)-based ferroelectric polymer. An ultrahigh electric field derived from the ferroelectric polarization can effectively modulate the band alignment of the GeSe/MoS heterojunction. Band alignment transition of the heterojunction from type II to type I is demonstrated. The combination of anisotropic GeSe with MoS realizes a high-performance polarization-sensitive photodetector exhibiting low dark current of approximately 1.5 pA, quick response of 14 μs, and high detectivity of 4.7 × 10 Jones. Dichroism ratios are also enhanced by ferroelectric polarization in a broad spectrum from visible to near-infrared. The ferroelectric-tuned GeSe/MoS van der Waals heterojunction has great potential for multifunctional detection applications in sophisticated light information sensing. More profoundly, the ferroelectric-tuned van der Waals heterojunction structure provides a valid band-engineering approach to creating versatile devices.
与大量二维材料的范德华集成提供了组装功能器件的广泛基础。在特定的范德华异质结中，能带排列工程对于实现高性能和多功能性至关重要且可行。在此，我们通过集成GeSe/MoS范德华异质结（VHJ）和聚（偏二氟乙烯 - 三氟乙烯）基铁电聚合物，设计了一种铁电调谐的范德华异质结器件结构。源自铁电极化的超高电场可有效调制GeSe/MoS异质结的能带排列。证明了异质结从II型到I型的能带排列转变。各向异性的GeSe与MoS的结合实现了一种高性能的偏振敏感光电探测器，其表现出约1.5 pA的低暗电流、14 μs的快速响应以及4.7×10琼斯的高探测率。在从可见光到近红外的宽光谱范围内，铁电极化也增强了二向色性比率。铁电调谐的GeSe/MoS范德华异质结在复杂光信息传感的多功能检测应用中具有巨大潜力。更深刻的是，铁电调谐的范德华异质结结构提供了一种有效的能带工程方法来制造多功能器件。
