Super-ballistic diffusion in a quasi-periodic non-Hermitian driven system with nonlinear interaction

We investigate the effects of nonlinear interactions on quantum diffusion in a quasi-periodic quantum kicked rotor system,featuring a non-Hermitian kicking potential.Remarkably,when the non-Hermitian driving strength is sufficiently strong,the energy diffusion follows a power law of time,characterized by an exponent that decreases monotonically with increasing the strength of nonlinear interactions.This demonstrates the emergence of super-ballistic diffusion(SBD).We find a distinct prethermalization stage in the time domain preceding the onset of SBD.The unique quantum diffusion phenomena observed in this chaotic system can be attributed to the decoherence effects generated by the interplay between nonlinear interactions and the non-Hermitian kicking potential.

Majorana zero modes,unconventional real-complex transition,and mobility edges in a one-dimensional non-Hermitian quasi-periodic lattice

A one-dimensional non-Hermitian quasiperiodic p-wave superconductor without PT-symmetry is studied.By analyzing the spectrum,we discovered that there still exists real-complex energy transition even if the inexistence of PT-symmetry breaking.By the inverse participation ratio,we constructed such a correspondence that pure real energies correspond to the extended states and complex energies correspond to the localized states,and this correspondence is precise and effective to detect the mobility edges.After investigating the topological properties,we arrived at a fact that the Majorana zero modes in this system are immune to the non-Hermiticity.

Characterizing entanglement in non-Hermitian chaotic systems via out-of-time ordered correlators

We investigate the quantum entanglement in a non-Hermitian kicking system.In the Hermitian case,the out-of-time ordered correlators(OTOCs)exhibit the unbounded power-law increase with time.Correspondingly,the linear entropy,which is a common measurement of entanglement,rapidly increases from zero to almost unity,indicating the formation of quantum entanglement.For strong enough non-Hermitian driving,both the OTOCs and linear entropy rapidly saturate as time evolves.Interestingly,with the increase of non-Hermitian kicking strength,the long-time averaged value of both OTOCs and linear entropy has the same transition point where they exhibit the sharp decrease from a plateau,demonstrating the disentanglment.We reveal the mechanism of disentanglement with the extension of Floquet theory to non-Hermitian systems.