Viscoelastic tensor and hydrodynamics of altermagnets

TL;DR

This paper derives the viscoelastic tensor for altermagnets and explores how their anisotropic Fermi surfaces influence hydrodynamic transport, revealing unique spin and charge flow behaviors that could aid experimental detection.

Contribution

It introduces the calculation of the viscoelastic tensor specific to altermagnets and formulates hydrodynamic equations accounting for their anisotropic properties.

Findings

Altermagnetic anisotropy modifies transport properties.

Spin and charge flows exhibit Poiseuille profiles.

Nonlocal responses are affected by anisotropic effects.

Abstract

We calculate the viscoelasticity tensor for altermagnets and formulate the corresponding hydrodynamic equations. The anisotropy of altermagnetic Fermi surfaces allows for additional terms in the viscoelasticity tensor and is manifested in transport properties, including electron and spin flows in a channel and nonlocal responses. In the channel geometry, the altermagnetic spin splitting leads to nontrivial spin density and spin current. Like the electric current, the spin current acquires a Poiseuille profile for no-slip boundary conditions. In nonlocal responses, the altermagnetic anisotropy affects current streamlines and electric potential distributions in the viscous regime. Our results provide signatures of the hydrodynamic transport regime in altermagnets, potentially facilitating its experimental studies and discovery.