A large inverse photoconductance based on an asymmetric Van der Waals Bi-heterostructure. (1st December 2022) - Chen, Yibo
Abstract: As a fundamental physical effect and a natural photoelectric response to light irradiation, traditional photoconductance (PC) is widely used in many aspects of our daily work and life. However, the lack of large inverse photoconductance (IPC) limits the development of optoelectronic technologies. This paper reports a large IPC with a ratio of 32.6 from an asymmetric Thin-graphene(Gr, ∼12 nm)/CsPbBr3 - p -GaN/Thick-Gr(∼24 nm) van der Waals bi-heterostructure under a low drive bias of 0.10 V and an irradiation of 360.0 nm laser. Adjusted by asymmetric Gr layers and enhanced by CsPbBr3, the IPC with short response/recovery times of ∼100.0 μs is originated from the asymmetric energy band of p -GaN surface under 360.0 nm laser irradiation. The large IPC, demonstrating its application as an optoelectronic TERNARY logic gate with simplification and diversity, provides a strategy to promote the development of optoelectronic technologies. Graphical Abstract: A Thin-Gr/CsPbBr3 - p -GaN/Thick-Gr van der Waals bi-heterostructure with different graphene thickness is designed and a large inverse photoconductance effect is realized under 360.0 nm laser irradiation (8.10 mW cm −2 ) and 0.10 V bias. Mechanism, properties and application of the device have been studied. ga1 Highlights: An excellent inverse photoconductance effect is obtained based on an asymmetric Thin-Gr/CsPbBr3- p -GaN/Thick-Gr bi-heterostructure. Large ratio of 32.6 and short response/recovery times of ~113.0/87.0 μs are achieved. The bi-heterostructure can work at normal atmosphere and bias of 0.10 V, which is beneficial for the need of integrate devices.