Reconfigurable Optoelectronic Logic Gates Enabled by a VSe2/MoTe2 van der Waals Heterojunction.

Abstract

Optoelectronic logic gates that integrate optical inputs with electrical outputs offer a promising route toward high-bandwidth, low-power in-sensor computing. However, most existing implementations require precise control over the excitation wavelength, optical power, or gate bias, which complicates device fabrication and system integration. Here, we demonstrate a reconfigurable optoelectronic logic device based on a VSe₂/MoTe₂ van der Waals heterojunction. The device exhibits a rectification ratio exceeding 10³ in the dark and a pronounced photovoltaic response, including a light on/off ratio surpassing 10⁷, a responsivity of 0.28 A/W, and external quantum efficiency of 54%, as well as a noise-equivalent power of 4.6 × 10^-14 W/Hz^1/2 and a specific detectivity of 2.1 × 10¹⁰ cm Hz^1/2/W. By reconfiguring the source and drain electrodes and modulating the optical input, six fundamental Boolean logic operations-AND, IMP, NOR, NOT, OR, and NAND-are realized in the device. Notably, all six logic functions are obtained under fixed illumination and predefined bias, without requiring wavelength, power, or gate modulation. Switching between functions requires only a specific bias voltage and a change in the source/drain connection (for certain operations, OR and NAND, the input state is redefined). These results underscore the promise of two-dimensional material-based van der Waals heterojunctions for compact, low-power, and reconfigurable optoelectronic logic processing.