Electrically switchable non-relativistic Zeeman spin splittings in collinear antiferromagnets

Abstract

Magnetic or electrical manipulation of electronic spin is elementary for spin-based logic, computing, and memory, where the latter is a low-power manipulation scheme. Rashba-like spin splittings stemming from spin-orbit interaction (SOI) enable electric-field manipulation of spin, but the relativistic SOI causes spin relaxations and yields dissipative transport of spin-encoded information. Recent works suggest the occurrence of electric-field switchable non-relativistic Zeeman spin splittings (NRZSSs) in collinear antiferromagnets -- allowing for electrical manipulation of spin in the non-relativistic regime; yet, a theory elucidating the mechanisms for these NRZSSs and guiding the materials discovery remains missing. Here, we develop such a theory by analyzing the symmetries of spin point groups. We highlight the linear magnetoelectric and bilinear piezomagnetoelectric mechanisms for NRZSSs that depend linearly on electric field and are electrically switchable. First-principles calculations further confirm that FeOOH and NaMnP showcase such NRZSSs. Our theory provides guidelines for discovering light-element collinear antiferromagnets with electrically switchable NRZSSs, which are promising for the design of high-performance spin-based devices.

Figures (3)

• Figure 1: Collinear magnetic structures for (a) FeOOH and (b) NaMnP antiferromagnets, where only the Fe and Mn sublattices are displayed. The cyan and pink spheres denote ions (Fe or Mn) with magnetic moments along $+\boldsymbol{\chi}$ and $-\boldsymbol{\chi}$ directions, respectively. In panels (a) and (b), the boxes enclosed by the black dashed lines represent the cells of FeOOH and NaMnP employed in our simulations. The primitive cell of NaMnP is sketched by the box with pink solid lines in panel (b).
• Figure 2: The electric-field switchable NRZSSs in FeOOH and NaMnP. Panels (a) and (b) are magnetoelectric NRZSSs in FeOOH driven by $E_x$, while panels (c) and (d) are piezomagnetoelectric NRZSSs in NaMnP driven by $E_z$ combined with $\eta_{xy}=4\%$. The red (blue) solid lines correspond to the spin-up (spin-down) states, and $\varepsilon_F$ denotes the Fermi level.
• Figure 3: The linear magnetoelectric $\Delta_1$ splittings in FeOOH and bilinear piezomagnetoelectric $\Delta_2$ splittings in NaMnP. Purple circles show $\Delta_1$ in FeOOH as a function of $E_x$; Blue squares show $\Delta_2$ in NaMnP as a function of $E_z$ (under a fixed strain of $\eta_{xy}=4\%$). Purple and blue lines display the corresponding linear regression results.