Fast and reliable identification of atomically thin layers of TaSe2 crystals

TL;DR

This paper presents a method for quickly and reliably identifying atomically thin TaSe2 layers using optical microscopy and Raman spectroscopy, aiding future research on their unique physical properties.

Contribution

It provides guidelines and optimal substrates for identifying ultrathin TaSe2 flakes, enhancing non-destructive characterization techniques.

Findings

Established optical and Raman signatures for ultrathin TaSe2

Identified substrates that improve optical identification

Enabled isolation of atomically thin TaSe2 layers

Abstract

Deposition of clean and defect-free atomically thin two-dimensional crystalline flakes on surfaces by mechanical exfoliation of layered bulk materials has proven to be a powerful technique, but it requires a fast, reliable and non-destructive way to identify the atomically thin flakes among a crowd of thick flakes. In this work, we provide general guidelines to identify ultrathin flakes of TaSe2 by means of optical microscopy and Raman spectroscopy. Additionally, we determine the optimal substrates to facilitate the optical identification of atomically thin TaSe2 crystals. Experimental realization and isolation of ultrathin layers of TaSe2 enables future studies on the role of the dimensionality in interesting phenomena such as superconductivity and charge density waves.