Quantum geometry and linear orbital response in arbitrary $SU(2)$ representation

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Atencia, Rhonald Burgos
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912910246150144
author Atencia, Rhonald Burgos
author_facet Atencia, Rhonald Burgos
contents We develop a unified framework to compute band-geometric quantities in multiband systems whose low-energy Hamiltonians realize arbitrary $SU(2)$ representations. Exploiting the presence of a quantization axis, we use the Wigner--Eckart theorem to identify the allowed interband matrix elements and obtain compact analytic expressions for the quantum geometric tensor, the orbital magnetic moment, and the resulting orbital transport coefficients. The formalism applies to both multifold fermions and gapped $SU(2)$ models. Its versatility is demonstrated through explicit calculations in representative $SU(3)$ and $SU(4)$ settings, where orbital Edelstein and orbital Hall responses arise naturally from the antisymmetric components of the band geometry. Our results reveal a universal link between the algebraic structure of the Hamiltonian and emergent orbitronic phenomena.
format Preprint
id arxiv_https___arxiv_org_abs_2512_04164
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Quantum geometry and linear orbital response in arbitrary $SU(2)$ representation
Atencia, Rhonald Burgos
Mesoscale and Nanoscale Physics
We develop a unified framework to compute band-geometric quantities in multiband systems whose low-energy Hamiltonians realize arbitrary $SU(2)$ representations. Exploiting the presence of a quantization axis, we use the Wigner--Eckart theorem to identify the allowed interband matrix elements and obtain compact analytic expressions for the quantum geometric tensor, the orbital magnetic moment, and the resulting orbital transport coefficients. The formalism applies to both multifold fermions and gapped $SU(2)$ models. Its versatility is demonstrated through explicit calculations in representative $SU(3)$ and $SU(4)$ settings, where orbital Edelstein and orbital Hall responses arise naturally from the antisymmetric components of the band geometry. Our results reveal a universal link between the algebraic structure of the Hamiltonian and emergent orbitronic phenomena.
title Quantum geometry and linear orbital response in arbitrary $SU(2)$ representation
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2512.04164