Inverse Chiral Phonon Zeeman Effect in Noncentrosymmetric Crystals

TL;DR

This paper develops a microscopic theory explaining how chiral phonons in noncentrosymmetric crystals induce an internal magnetic field that affects electronic spins, revealing a lattice-driven inverse chiral phonon Zeeman effect.

Contribution

It introduces a novel microscopic model linking chiral phonons to spin polarization via dynamical piezoelectricity in noncentrosymmetric crystals.

Findings

Chiral phonons generate an elliptically polarized magnetic field.

The magnetic field acts as a Zeeman field on electronic spins.

The mechanism is effective in high-frequency Floquet regimes.

Abstract

We present a microscopic theory of the inverse chiral phonon Zeeman effect in noncentrosymmetric crystals. Within micropolar elasticity, coupled translational displacements and microrotations give rise to intrinsically chiral phonons, which generate an elliptically polarized internal magnetic field through dynamical piezoelectricity. In the high-frequency Floquet regime and under incomplete electronic screening, this field acts as an effective longitudinal Zeeman field on electronic spins, leading to spin polarization and band splitting. The results establish a purely lattice-driven mechanism for the inverse chiral phonon Zeeman effect in noncentrosymmetric crystals.