Logo image
Ferroelectric-Tunable Photoresponse in α-In2Se3 Photovoltaic Photodetectors: An Ab Initio Quantum Transport Study
 

Ferroelectric-Tunable Photoresponse in α-In2Se3 Photovoltaic Photodetectors: An Ab Initio Quantum Transport Study

Shibo Fang, Chen Yang, Qiuhui Li, Baochun Wu, Linqiang Xu, Shiqi Liu, Jie Yang, Jiachen Ma, Jichao Dong, Ying Li, …
Physical review applied, Vol.19(2), 024024
08/02/2023
: https://doi.org/10.1103/PhysRevApplied.19.024024
Physical Sciences Physics Physics, Applied Science & Technology
Two-dimensional alpha-In2Se3 has drawn broad attention due to its high photoresponse and unique roomtemperature interlocked in-plane and out-of-plane ferroelectricity with an ultralow switching electric field. Here, we investigate the photoresponse in a lateral monolayer (ML) alpha-In2Se3 p-i-n junction by using ab initio quantum transport simulations. The maximum photoresponses of the lateral alpha-In2Se3 p-i-n junction are up to 69.2 and 31.6 mA/W for the ferroelectric wurtzite and zincblende phases (shortly named WZ' and ZB') alpha-In2Se3, respectively, which are 8-17 times higher than that of the extensively researched graphene photodetector (4 mA/W). Remarkably, the ferroelectric photoresponses, defined as the photoresponse change ratio between the two ferroelectric states, of the lateral ML WZ' and ZB'-In2Se3 photodetectors have average values of 127% and 121% with surprising maximum values of 2 x 106% and 1 x 107%, respectively. The physical mechanism comes from the electron density redistribution altered by the atomic displacements due to the polarization switch, rather than the built-in potential change induced by the surface polarization charges. Such ferroelectric-tunable photoresponses in the alpha-In2Se3 photodetector suggest a potential in the fabrication of future optical detection and storage integrated devices.
1
Logo image