2026, Twist-angle-controlled built-in field reversal enables programmable self-powered photodetection in low-symmetry heterostructures , Nano Letters.

2026, Twist-angle-controlled built-in field reversal enables programmable self-powered photodetection in low-symmetry heterostructures , Nano Letters.

Abstract:

Interfacial electric fields govern charge separation in van der Waals photodetectors, yet they are typically modulated by electrostatic gates or ferroelectric interlayers, which introduce power consumption and stability challenges. Here we show that twist angle intrinsically controls interfacial electrostatics in low-symmetry ReS₂/ReSe₂ heterostructure. Rotating the anisotropic crystal axes reconstructs the interfacial polarization landscape, leading to a reversal of the built-in electric field in the orthogonal stacking configuration. This enables efficient self-powered photodetection with an on/off ratio of 10⁵ and high responsivity. Twist-controlled electrostatic reconstruction further modulates carrier separation and anisotropic transport, transforming the polarization-dependent photocurrent from a two-lobed to an approximately four-lobed profile, enabling tunable polarization sensitivity. Moreover, the deterministic twist-angle-dependent photocurrent allows hardware-level encoding. These results establish twist engineering as an effective strategy for tailoring interfacial fields and multifunctional optoelectronic responses in low-symmetry van der Waals heterostructures.

Keywords: Twist angle, van der Waals Heterostructure, self-powered photodetection, low-symmetry interface.

Link: https://pubs.acs.org/doi/full/10.1021/acs.nanolett.6c02233

twist-angle-controlled-built-in-field-reversal-enables-programmable-self-powered-photodetection-in-low-symmetry.pdf