Surface Luttinger arcs in Weyl semimetals

Abstract

Weyl semimetals famously host a surface topological metal containing open Fermi arcs instead of closed Fermi surfaces. Here, the authors predict another surface feature, Luttinger arcs, that form closed loops with the Fermi arcs in undoped Weyl semimetals. Luttinger arcs are common, albeit experimentally inaccessible, for strongly interacting electrons. Here, they occur even without interactions and switch places with Fermi arcs for different surface terminations -- a property the authors exploit to pinpoint Luttinger arcs for Co and Sn terminations in Co${}_{3}$Sn${}_{2}$S${}_{2}$.