Reconfigurable Optoelectronic Logic Gates With Wavelength-Dependent Bipolar Photoresponse From ReS2/Gr/h-BN/Gr Heterojunctions.

With the rapid growth of optical computing and integrated photonics, low-power optoelectronic logic devices are essential for on-chip information processing. Conventional implementations rely on multiple discrete components, limiting system scalability. We demonstrate a wavelength-dependent bipolar optoelectronic logic device based on a ReS2/Gr/h-BN/Gr van der Waals heterostructure. The fundamental mechanism is VOC-dictated: under 365 nm illumination, a substantial VOC magnitude defines a high-capacity absorption response and a photovoltaic (PV) process, generating a negative photocurrent. In contrast, at 635 nm, a diminished VOC restricts the absorption response strength, yielding a positive photocurrent and enabling reversible PV polarity switching. This bipolarity is key to achieving "single-device multifunctional logic." By adjusting wavelength and power, a single physical unit reconfigures six fundamental logic gates (OR, AND, NOR, NAND, NOT, and XNOR), reducing the transistor count required for complex circuits by 87.5% compared to CMOS implementations. The device exhibits high responsivity (730 mA/W at 365 nm; 490 mA/W at 635 nm), a detectivity of 1011 Jones, ultralow dark current of 15 pA, and sub-microsecond working speed. This VOC-driven reconfigurable logic offers a compact, energy-efficient pathway for integrated photonics and secure optical communication.