Light-programmable reorientation of the crystallographic c-axis of Tellurium thin films

TL;DR

This paper introduces a non-contact, light-based technique to dynamically and reversibly reorient the crystallographic c-axis of tellurium thin films, enabling programmable anisotropy for advanced optoelectronic applications.

Contribution

It presents a novel method using polarized picosecond laser pulses to controllably reorient tellurium's c-axis, overcoming limitations of traditional synthesis techniques.

Findings

c-axis can be omnidirectionally reoriented perpendicular to laser polarization

Reorientation is fully reversible and rewritable

Enables programmable anisotropy for optoelectronic devices

Abstract

Tellurium (Te), a two-dimensional material with pronounced structural anisotropy, exhibits exceptional electrical and optical properties that are highly sensitive to its crystallographic orientation. However, conventional synthesis techniques offer limited control over the in-plane alignment of Te's crystallographic c-axis, hindering large-scale integration. Here, we report a novel, non-contact method to dynamically manipulate the c-axis orientation of Te thin films using linearly polarized picosecond laser pulses. We show that the c-axis can be omnidirectionally reoriented perpendicular to the laser polarization, even in initially polycrystalline films. This reorientation is fully reversible, allowing for rewritable and spatially selective control of the c-axis orientation post-deposition. Our light-driven approach enables programmable anisotropy in Te, opening new avenues for reconfigurable optoelectronic and photonic devices, such as active metasurfaces and CMOS-compatible architectures.