Peierls Transition and Magnetism in a Dirac Semimetal: CaMnBi 2
The research investigated anomalies in CaMnBi2 near 50 K, ruling out magnetic causes like spin canting. Instead, it found a coupled structural and magnetic transition at T* = 46(2) K. This transition is driven by an electronically induced Peierls instability, where the Dirac electrons undergo a bond-order wave modulation in the Bi layer.