Gauge Symmetry as the Origin of Spin-Orbit Coupling of Light

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Yang, Lili, Feng, Longlong, Zhang, Pengming
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908891757936640
author Yang, Lili
Feng, Longlong
Zhang, Pengming
author_facet Yang, Lili
Feng, Longlong
Zhang, Pengming
contents Dual symmetry is an intrinsic property of Maxwell's equations, corresponding to a global U(1) symmetry in vacuum, with helicity as the associated conserved quantity. In this paper, we investigate light propagation in a spin-degenerate medium using a field-theoretical approach and introduce an effective gauge field A_s that emerges from the localization of dual symmetry. Within the geometric optics approximation, we show that the helical trajectory of light rays reveals this gauge field as a manifestation of spin-orbit coupling. Although orbital-orbit coupling also arises in such systems, the spin-orbit interaction possesses deeper physical significance, as it originates from the intrinsic dual symmetry embedded in Maxwell's equations.
format Preprint
id arxiv_https___arxiv_org_abs_2504_19501
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Gauge Symmetry as the Origin of Spin-Orbit Coupling of Light
Yang, Lili
Feng, Longlong
Zhang, Pengming
Optics
Dual symmetry is an intrinsic property of Maxwell's equations, corresponding to a global U(1) symmetry in vacuum, with helicity as the associated conserved quantity. In this paper, we investigate light propagation in a spin-degenerate medium using a field-theoretical approach and introduce an effective gauge field A_s that emerges from the localization of dual symmetry. Within the geometric optics approximation, we show that the helical trajectory of light rays reveals this gauge field as a manifestation of spin-orbit coupling. Although orbital-orbit coupling also arises in such systems, the spin-orbit interaction possesses deeper physical significance, as it originates from the intrinsic dual symmetry embedded in Maxwell's equations.
title Gauge Symmetry as the Origin of Spin-Orbit Coupling of Light
topic Optics
url https://arxiv.org/abs/2504.19501