X-ray study settles debate on chiral phonons in quartz.

Researchers have settled the debate on whether phonons can be chiral, a fundamental concept in physics. Phonons are quasiparticles that describe the collective vibrational excitations of atoms in a crystal lattice. Using circular X-ray light, researchers at Paul Scherrer Institute PSI showed that phonons can twist like a corkscrew through quartz, demonstrating chirality. This discovery could have important implications for the fundamental physical properties of materials, particularly in the field of topological materials.