# Strain Engineering of Correlated Charge-Ordered Phases in 1T-TaS2

## TL;DR

This paper shows how strain can control charge density wave phases in 1T-TaS2, enabling strain and displacement sensing at room temperature.

## Contribution

The study demonstrates strain-dependent modulation of CDW phase transitions in 1T-TaS2 using a device-compatible platform.

## Key findings

- Uniaxial strain reversibly alters the NC-CDW phase transition in 1T-TaS2.
- Resistance and threshold voltage show a quadratic strain dependence due to piezoresistive effects.
- A room-temperature strain sensor with threshold-like response is demonstrated using 1T-TaS2.

## Abstract

Strain engineering
is a powerful strategy for controlling the structural
and electronic properties of two-dimensional materials, particularly
in systems hosting charge density wave (CDW) order. In this work,
we apply uniaxial tensile and compressive strain to thin 1T-TaS2 flakes using a flexible, device-compatible platform and systematically
investigate the strain-dependent behavior of the nearly commensurate
(NC) to incommensurate (IC) CDW phase transition. This transition
is driven by Joule heating at room temperature. Electrical transport
measurements reveal that both the switching threshold voltage and
the resistance of the NC-CDW phase exhibit clear, reversible strain
dependence. Furthermore, we identify a quadratic dependence between
the strain-induced resistance change and the threshold voltage, confirming
that piezoresistive modulation governs the strain tunability of the
phase transition. We demonstrate a room-temperature, electrical readout
strain and displacement sensor with a threshold-like response in a
programmable window. These results highlight the potential of 1T-TaS2 for on-chip sensing of strain and displacement.