Complex charge density waves in simple electronic systems of two-dimensional III₂-VI₃ materials.

ABSTRACT: Charge density wave (CDW) is the phenomenon of a material that undergoes a spontaneous lattice distortion and modulation of the electron density. Typically, the formation of CDW is attributed to Fermi surface nesting or electron-phonon coupling, where the CDW vector (Q_CDW) corresponds to localized extreme points of electronic susceptibility or imaginary phonon frequencies. Here, we propose a new family of multiple CDW orders, including chiral Star-of-David configuration in nine 2D III₂-VI₃ van der Waals materials, backed by first-principles calculations. The distinct feature of this system is the presence of large and flat imaginary frequencies in the optical phonon branch across the Brillouin zone, which facilitates the formation of the diverse CDW phases.

SUBMITTER: Huang YT 

PROVIDER: S-EPMC11574180 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature