Radial spin texture in elemental tellurium with chiral crystal structure

TL;DR

This study reveals the spin textures in elemental tellurium's chiral crystal structure, showing spin-momentum locking and chirality-dependent spin polarization, which could lead to novel magnetoelectric and nonreciprocal effects.

Contribution

First direct investigation of spin textures in elemental tellurium's chiral structure using spin-resolved photoemission spectroscopy, demonstrating chirality-dependent spin polarization.

Findings

Spin component parallel to electron momentum around BZ corners.

Reversal of spin polarization with opposite chirality.

Hedgehog-like spin textures in chiral tellurium.

Abstract

The chiral crystal is characterized by a lack of mirror symmetry and an inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric crystal structure, the spin and momentum of electrons are locked in the reciprocal space with the help of the spin-orbit interaction. To reveal the spin textures of chiral crystals, here we investigate the spin and electronic structure in p-type semiconductor elemental tellurium with a chiral crystal structure by using spin- and angle-resolved photoemission spectroscopy. Our data demonstrate that the highest valence band crossing the Fermi level has a spin component parallel to the electron momentum around the BZ corners. Significantly, we have also confirmed that the spin polarization is reversed in the crystal with the opposite chirality. The results indicate that the spin textures of the right- and left-handed chiral crystals are hedgehog-like, leading to unconventional magnetoelectric effects and nonreciprocal phenomena.