Low-Frequency Noise Spectroscopy of Charge-Density-Wave Phase Transitions in Vertical Quasi-2D Devices

TL;DR

This study uses low-frequency noise spectroscopy to investigate charge-density-wave phase transitions in vertical quasi-2D 1T-TaS2 devices, revealing peaks associated with phase changes and potential hidden transitions.

Contribution

It demonstrates the effectiveness of noise spectroscopy in detecting phase transitions and hidden states in quasi-2D charge-density-wave materials.

Findings

Noise spectral density peaks align with resistance steps.

Some peaks occur below the known CDW transition temperature.

Potential detection of hidden phase transitions.

Abstract

We report results regarding the electron transport in vertical quasi-2D layered 1T-TaS2 charge-density-wave devices. The low-frequency noise spectroscopy was used as a tool to study changes in the cross-plane electrical characteristics of the quasi-2D material below room temperature. The noise spectral density revealed strong peaks - changing by more than an order-of-magnitude - at the temperatures closely matching the electrical resistance steps. Some of the noise peaks appeared below the temperature of the commensurate to nearly-commensurate charge-density-wave transition, possibly indicating the presence of the debated "hidden" phase transitions. These results confirm the potential of the noise spectroscopy for investigations of electron transport and phase transitions in novel materials.