132 citations · 675 across the 18 of their papers we have counts for
4 papers · 1 filter
Violation and Revival of Kramers' Degeneracy in Open Quantum Systems
Pengfei Zhang, Yu Chen
Kramers' theorem ensures double degeneracy in the energy spectrum of a time-reversal symmetric fermionic system with half-integer total spin. Here we are now trying to go beyond th…
Stability of Time-Reversal Symmetry Protected Topological Phases
Tian-Shu Deng, Lei Pan, Yu Chen +1
In a closed system, it is well known that the time-reversal symmetry can lead to Kramers degeneracy and protect nontrivial topological states such as quantum spin Hall insulator. I…
Constraints on the energy spectrum of non-Hermitian models in open environments
Jonatan Melkær Midtgaard, Zhigang Wu, Yu Chen
Motivated by recent progress on non-Hermitian topological band theories, we study the energy spectrum of a generic two-band non-Hermitian Hamiltonian. We prove rigorously that the…
Hall Conductance of a Non-Hermitian Chern Insulator
Yu Chen, Hui Zhai
In this letter we study the Hall conductance for a non-Hermitian Chern insulator and quantitatively describe how the Hall conductance deviates from a quantized value. We show the e…