Persistent anomaly in dynamical quantum phase transition in long-range non-Hermitian p-wave Kitaev chain

Considering a non-Hermitian version of p-wave Kitaev chain in the presence of additional second nearest neighbour tunnelling, we study dynamical quantum phase transition (DQPT) which accounts for the vanishing Loschmidt amplitude. The locus of the Fisher’s zero traces a continuous path on the complex time plane for the Hermitian case while it becomes discontinuous for non-Hermitian cases. This further leads to the half-unit jumps in the winding number characterizing a dynamical topological aspect of DQPT for non-Hermitian Hamiltonian. Uncovering the interplay between non-Hermiticity and long-range tunnelling, we find these features to be universally present irrespective of the additional second nearest neighbour tunnelling terms as long as non-Hermiticity is preserved. The upper panel depicts the discontinuity in Fisher’s zeros exactly on the imaginary axis. The lower panel demonstrates the half-qunatized jumps in the dynamical winding number corresponding to such discontinuous jump.