Two-color Kerr microscopy of two-dimensional materials with sub-picosecond time resolution

TL;DR

This paper introduces a two-color Kerr microscopy system with sub-picosecond time resolution and high spatial sensitivity, enabling detailed study of spin and valley dynamics in two-dimensional materials like MoS2.

Contribution

The work presents a novel microscopy system combining synchronized erbium-fiber lasers with tunable emission, achieving high spatial and temporal resolution for 2D material analysis.

Findings

Successful imaging of monolayer MoS2 dynamics

High sensitivity at cryogenic temperatures

Sub-picosecond temporal resolution achieved

Abstract

We present a two-color Kerr microscopy system based on two electronically synchronized erbium-fiber laser oscillators with independently tunable emission energies spanning most of the visible spectrum. Combining a spatial resolution below 2 $\mu$m and sub-ps time resolution with high sensitivity and cryogenic sample temperatures, it is ideally suited for studying spin and valley dynamics in a wide range of two-dimensional materials. We illustrate its capabilities by studying a monolayer of the common semiconducting transition metal disulfide MoS$_2$.