Physical Review Letters

The chiral crystal is characterized by a lack of mirror symmetry and inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric crystal structure, the spin and momentum of electrons are expected to be locked in the reciprocal space with the help of the spin-orbit interaction. To reveal the spin textures of chiral crystals, we investigate the spin and electronic structure in a p-type semiconductor, elemental tellurium, with the simplest chiral 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 Brillouin zone 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 hedgehoglike, leading to unconventional magnetoelectric effects and nonreciprocal phenomena.Received 21 November 2019Accepted 10 February 2020DOI:https://doi.org/10.1103/PhysRevLett.124.136404© 2020 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasSpin-orbit couplingPhysical SystemsElemental semiconductorsTechniquesAngle-resolved photoemission spectroscopySpin-resolved photoemission spectroscopyCondensed Matter & Materials Physics

Radial Spin Texture in Elemental Tellurium with Chiral Crystal Structure