Emergent $\mathcal{P}\mathcal{T}$-symmetry breaking of collective modes with topological critical phenomena

Jian-Song Pan, Wei Yi, Jiangbin Gong

The spontaneous breaking of parity-time ($\mathcal{P}\mathcal{T}$) symmetry yields rich critical behavior in non-Hermitian systems, and has stimulated much interest, albeit most previous stu…