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arXiv · 2108.00684

Electrically tunable room-temperature ferromagnetism in CrBr$_3$

Chandan K. Singh·Mukul Kabir
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Abstract

The recent discovery of magnetic ordering in two-dimension has lead to colossal efforts to find atomically thin materials that order at high temperatures. However, due to fundamental spin fluctuation in reduced dimension, the room-temperature ferromagnetism remains elusive. Here, we report a dramatic manipulation of magnetic ordering up to room temperature in the monolayer CrBr$_3$, within the first-principles Heisenberg XXZ model. The exchange and anisotropic magnetic interactions are externally modulated by a gate-induced charge carrier doping that triggers a nontrivial phase diagram. High-temperature ferromagnetism is associated with a substantial increase in both effective ferromagnetic exchange and overall magnetic anisotropy under experimentally attainable hole doping. In contrast, electron doping quickly switches the magnetic easy axis. The gate-tuneable room temperature ferromagnetism in CrBr$_3$ presents new possibilities in electrically controlled spintronic and magnetoelectric devices based on atomically thin crystals.

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Chandan K. Singh, Mukul Kabir. 2021-08-02. Electrically tunable room-temperature ferromagnetism in CrBr$_3$. https://doi.org/10.1103/physrevmaterials.6.084407

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