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arXiv · 2304.04393

Intrinsic persistent spin helix in 2D T-XY (X$\neq$Y=P, As, Sb and Bi)

San-Dong Guo·Xu-Kun Feng·Dong Huang·Shaobo Chen·Yee Sin Ang
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Abstract

The persistent spin helix (PSH) is robust against spin-independent scattering and renders an extremely long spin lifetime, which can improve the performance of potential spintronic devices. To achieve the PSH, a unidirectional spin configuration is required in the momentum space. Here, T-XY (X$\neq$Y=P, As, Sb and Bi) monolayers with dynamical, mechanical and thermal stabilities are predicted to intrinsically possess PSH. Due to the $C_{2\upsilon}$ point-group symmetry, a unidirectional spin configuration is preserved in the out-of-plane direction for both conduction and valence bands around the high-symmetry $\Gamma$ point. That is, the expectation value of the spin $S$ only has the out-of-plane component $S_z$. The application of an out-of-plane external electric field can induce in-plane components $S_x$ and $S_y$, thus offering a promising platform for the on-off logical functionality of spin devices. Our work reveals a new family of T-phase two-dimensional (2D) materials, which could provide promising applications in spintronic devices.

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San-Dong Guo, Xu-Kun Feng, Dong Huang, Shaobo Chen, Yee Sin Ang. 2023-04-10. Intrinsic persistent spin helix in 2D T-XY (X$\neq$Y=P, As, Sb and Bi). https://arxiv.org/abs/2304.04393

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