Antiferromagnetic spin Seebeck effect across the spin-flop transition: A stochastic Ginzburg-Landau simulation

Abstract

We investigate the antiferromagnetic spin Seebeck effect across the spin-flop transition in a numerical simulation based on the time-dependent Ginzburg-Landau equation for a bilayer of a uniaxial insulating antiferromagnet and an adjacent metal. By directly simulating the rate of change of the conduction-electron spin density $\mathbf{s}$ in the adjacent metal layer, we demonstrate that a sign reversal of the antiferromagnetic spin Seebeck effect across the spin-flop transition occurs when the interfacial coupling of $\mathbf{s}$ to the staggered magnetization $\mathbf{n}$ of the antiferromagnet dominates, whereas no sign reversal appears when the interfacial coupling of $\mathbf{s}$ to the magnetization $\mathbf{m}$ dominates. Moreover, we show that the sign reversal is influenced by the degree of spin dephasing in the metal layer. Our result indicates that the sign reversal is not a generic property of a simple uniaxial antiferromagnet, but controlled by microscopic details of the exchange coupling at the interface and the spin dephasing in the metal layer.

15 pages, 6 figures

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Cited by in corpus (2)

• Magnon drag induced by magnon-magnon interactions characteristic of noncollinear magnets
• Spin Seebeck in the weak exchange coupled van der Waals antiferromagnet