Room-temperature non-volatile optical manipulation of polar order in a charge density wave

TL;DR

This study demonstrates room-temperature, non-volatile, all-optical control of polar order in a charge density wave material, enabling reversible electronic state manipulation with potential for ultrafast electronic devices.

Contribution

It introduces a novel method for reversible, non-volatile optical manipulation of electronic polar states in EuTe4 at room temperature, highlighting layer-specific phase dynamics.

Findings

Reversible optical control alters electrical resistance and second harmonic generation.

Layer-dependent phase inversion mediates polar order manipulation.

Control achieved at ambient conditions with ultrafast laser excitation.

Abstract

Utilizing ultrafast light-matter interaction to manipulate electronic states of quantum materials is an emerging area of research in condensed matter physics. It has significant implications for the development of future ultrafast electronic devices. However, the ability to induce long-lasting metastable electronic states in a fully reversible manner is a long-standing challenge.Here, by using ultrafast laser excitations, we demonstrate the capability to manipulate the electronic polar states in the charge-density-wavematerial EuTe4 in a non-volatile manner. The process is completely reversible and is achieved at room temperature with an all-optical approach. Each induced non-volatile state brings about modifications to the electrical resistance and second harmonic generation intensity. The results point to layer-specific phase inversion dynamics by which photoexcitation mediates the stacking polar order of the system. Our findings extend the scope of non-volatile all-optical control of electronic states to ambient conditions, and highlight a distinct role of layerdependent phase manipulation in quasi-two-dimensional systems with inherent sublayer stacking orders.