Electric-field control of magnetism in few-layered van der Waals magnet

TL;DR

This paper demonstrates electric-field control of magnetism in few-layered van der Waals Cr$_{2}$Ge$_{2}$Te$_{6}$ devices using ionic gating, showing tunable magnetization and opening avenues for spintronics and magnetic memory applications.

Contribution

It provides the first clear evidence of gate-tunable magnetism in van der Waals layered semiconductors through ionic gating techniques.

Findings

Strong field effect observed via ionic gating.

Tunable magnetization loops below Curie temperature.

Potential for applications in spintronics and magnetic memory.

Abstract

Manipulating quantum state via electrostatic gating has been intriguing for many model systems in nanoelectronics. When it comes to the question of controlling the electron spins, more specifically, the magnetism of a system, tuning with electric field has been proven to be elusive. Recently, magnetic layered semiconductors have attracted much attention due to their emerging new physical phenomena. However, challenges still remain in the demonstration of a gate controllable magnetism based on them. Here, we show that, via ionic gating, strong field effect can be observed in few-layered semiconducting Cr$_{2}$Ge$_{2}$Te$_{6}$ devices. At different gate doping, micro-area Kerr measurements in the studied devices demonstrate tunable magnetization loops below the Curie temperature, which is tentatively attributed to the moment re-balance in the spin-polarized band structure. Our findings of electric-field controlled magnetism in van der Waals magnets pave the way for potential applications in new generation magnetic memory storage, sensors, and spintronics.