Spin band geometry drives intrinsic thermal spin magnetization and current

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Sarkar, Sankar, Varshney, Harsh, Sarkar, Sayan, Agarwal, Amit
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912605040279552
author Sarkar, Sankar
Varshney, Harsh
Sarkar, Sayan
Agarwal, Amit
author_facet Sarkar, Sankar
Varshney, Harsh
Sarkar, Sayan
Agarwal, Amit
contents Generating spin magnetization and spin currents without magnetic or electric fields is a key frontier in spin caloritronics. Spin responses driven by thermal gradients offer a promising route, though the band geometric origin of intrinsic mechanisms, especially in non-magnetic materials, remains poorly understood. Here we develop a unified quantum theory of thermal spin magnetization and spin currents in itinerant electrons, rooted in spin band geometry with both Fermi-surface and Fermi-sea contributions. We identify two key geometric quantities: the spin-velocity metric tensor, which governs thermal spin magnetization, and the spin geometric tensor, combining spin Berry curvature and spin quantum metric, which generates thermal spin currents. These intrinsic contributions persist and can even dominate in non-magnetic insulators. Numerical calculations for chiral metal RhGe and antiferromagnet CuMnAs demonstrate sizable thermal spin responses near band crossings. Our results establish the band geometric origin of thermal spin transport and provide guiding principles for discovering and engineering next-generation spin caloritronic materials.
format Preprint
id arxiv_https___arxiv_org_abs_2509_21215
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Spin band geometry drives intrinsic thermal spin magnetization and current
Sarkar, Sankar
Varshney, Harsh
Sarkar, Sayan
Agarwal, Amit
Mesoscale and Nanoscale Physics
Materials Science
Generating spin magnetization and spin currents without magnetic or electric fields is a key frontier in spin caloritronics. Spin responses driven by thermal gradients offer a promising route, though the band geometric origin of intrinsic mechanisms, especially in non-magnetic materials, remains poorly understood. Here we develop a unified quantum theory of thermal spin magnetization and spin currents in itinerant electrons, rooted in spin band geometry with both Fermi-surface and Fermi-sea contributions. We identify two key geometric quantities: the spin-velocity metric tensor, which governs thermal spin magnetization, and the spin geometric tensor, combining spin Berry curvature and spin quantum metric, which generates thermal spin currents. These intrinsic contributions persist and can even dominate in non-magnetic insulators. Numerical calculations for chiral metal RhGe and antiferromagnet CuMnAs demonstrate sizable thermal spin responses near band crossings. Our results establish the band geometric origin of thermal spin transport and provide guiding principles for discovering and engineering next-generation spin caloritronic materials.
title Spin band geometry drives intrinsic thermal spin magnetization and current
topic Mesoscale and Nanoscale Physics
Materials Science
url https://arxiv.org/abs/2509.21215