A multimode photodetector with polarization-dependent near-infrared responsivity using the tunable split-dual gates control

Zhou Zhang; Junxin Chen; Hao Jia; Jianfa Chen; Feng Li; Ximiao Wang; Shaojing Liu; Hai Ou; Song Liu; Huanjun Chen; Ya-Qing Bie; Shaozhi Deng

doi:10.1016/j.isci.2022.105164

A multimode photodetector with polarization-dependent near-infrared responsivity using the tunable split-dual gates control

iScience. 2022 Sep 19;25(10):105164. doi: 10.1016/j.isci.2022.105164. eCollection 2022 Oct 21.

Authors

Zhou Zhang^{1

2}, Junxin Chen^{1

2}, Hao Jia³, Jianfa Chen¹, Feng Li^{1

2}, Ximiao Wang^{1

2}, Shaojing Liu^{1

2}, Hai Ou^{1

2}, Song Liu³, Huanjun Chen^{1

2}, Ya-Qing Bie^{1

2}, Shaozhi Deng^{1

2}

Affiliations

¹ School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510006, China.
² State Key Lab of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, Sun Yat-sen University, Guangzhou 510006, China.
³ Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.

Abstract

As the limited carrier densities in atomic thin materials can be well controlled by electrostatic gates, p-n junctions based on two-dimensional materials in the coplanar split-gate configuration can work as photodetectors or light-emitting diodes. These coplanar gates can be fabricated in a simple one-step lithography process and are frequently used in hybrid integration with on-chip optical structures. However, the polarization-dependent responsivity of such a configuration is less explored in the near-infrared band, and a clear understanding is still missing. Here we fabricate near-infrared tunable multiple modes twisted bilayer graphene photodetector enabled by the coplanar split-gate control and confirm that the photothermoelectric effect governs the photovoltage mechanism of the p-n junction mode. Our study also elucidates that the discrepancy of the responsivities under different linear polarizations is owing to the different cavity modes and provides a valuable example for designing chip-integrated optoelectronic devices.

Keywords: Electronic materials; Nanomaterials; Optical materials.