Quartic metal: Spontaneous breaking of time-reversal symmetry due to four-fermion correlations in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$

Vadim Grinenko, Daniel Weston, Federico Caglieris +19

Discoveries of ordered quantum states of matter are of great fundamental interest, and often lead to unique applications. The most well known example -- superconductivity -- is cau…