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arXiv · 2607.03544

Nonlocal Orbital-Angular-Momentum Dichroism of Vortex Light in Strained Crystals

Habib Rostami
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Abstract

Vortex light carries orbital angular momentum (OAM) in its transverse phase. We show that the transverse phase cannot generate OAM-odd absorption in any continuously translation-invariant system, even when optical nonlocality and multipole light--matter coupling are included. The combination of broken continuous translation symmetry and finite-range optical nonlocality permits OAM dichroism through transverse-momentum mixing; in nonuniformly strained Dirac materials, the dichroism factorizes into a nonlocal elasto-optic tensor and the overlap of the strain texture with the vortex transverse phase current.

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Habib Rostami. 2026-07-03. Nonlocal Orbital-Angular-Momentum Dichroism of Vortex Light in Strained Crystals. https://arxiv.org/abs/2607.03544

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