New research uncovers chiral topological phases in metals without structural order

Fermions are among the most important particles in physics and include both everyday electrons and more exotic variants. Chiral fermions, like gloves, come in left- and right-handed versions and were proposed over a century ago. While high-energy neutrinos—the leading candidates for massless chiral fermions—proved to have mass, nearly (semi-) metallic solid-state crystals were discovered 15 years ago to host electronic versions of massless chiral fermions.