The unidirectional Seebeck detection of the Néel vector in the two-dimensional tetragonal $\mathcal{P}\mathcal{T}$-symmetric antiferromagnetic materials

Abstract

The efficient detection of the reversal (180${}^{\circ }$ rotation) of the Néel vector is one of the crucial tasks in antiferromagnetic spintronics. Here, we propose a thermal approach to detect the reversal of the Néel vector in the tetragonal $\mathcal{P}\mathcal{T}$ antiferromagnetic materials through the unidirectional Seebeck effect (USE). Being different from the previous works in which USE stems from the global Rashba spin-orbit coupling (SOC) or asymmetric magnon scattering, we find that the USE originates from the coupling of the hidden Rashba SOC and the Néel vector in the tetragonal $\mathcal{P}\mathcal{T}$ antiferromagnetic materials in the absence of the global Rashba SOC. Using a generic minimal model, we analyse the behaviors of the USE for the two-dimensional tetragonal lattice $\mathcal{P}\mathcal{T}$ antiferromagnet. Importantly, It's found that when the Néel vector is reversed, the sign of the USE changes, which can be utilized to detect the reversal of the Néel vector.

9 pages, 2 figures,Accepted by PRB