Truly Chiral Phonons Observed in Three-Dimensional Materials for the First Time

Chirality can be true or false, depending on the symmetry of dynamic propagation. Crystal lattice vibrations, called phonons, can also display chirality as has been shown in some two-dimensional structures. However, truly chiral phonons have never been observed in three-dimensional systems—that is, until now. Researchers from Tokyo Tech have identified these for the first time, in bulk cinnabar. Utilizing pseudo-angular momentum, their method can be used to identify the chirality in crystalline structures.

• Truly Chiral Phonons Observed in Three-Dimensional Materials for the First Time