Information retrieval and eigenstates coalescence in a non-Hermitian quantum system with anti-$\mathcal{P}\mathcal{T}$ symmetry

Abstract

Non-Hermitian systems with parity-time reversal ($\mathcal{P}\mathcal{T}$) or anti-$\mathcal{P}\mathcal{T}$ symmetry have attracted a wide range of interest owing to their unique characteristics and counterintuitive phenomena. One of the most extraordinary features is the presence of an exception point (EP), across which a phase transition with spontaneously broken $\mathcal{P}\mathcal{T}$ symmetry takes place. We implement a Floquet Hamiltonian of a single qubit with anti-$\mathcal{P}\mathcal{T}$ symmetry by periodically driving a dissipative quantum system of a single trapped ion. With stroboscopic emission and quantum state tomography, we obtain the time evolution of density matrix for an arbitrary initial state, and directly demonstrate information retrieval, eigenstates coalescence, and topological energy spectra as unique features of non-Hermitian systems.

6 pages, 5 figures

References in corpus (3)

• Reversing the Pump-Dependence of a Laser at an Exceptional Point
• Observation of parity-time symmetry breaking in a single spin system
• Chirality of wave functions for three coalescing levels

Cited by in corpus (11)

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• Encircling the Liouvillian exceptional points: a brief review
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• Photonic chiral state transfer near the Liouvillian exceptional point
• Quantum Mpemba effect in parity-time symmetric systems
• Engineering nonequilibrium steady states through Floquet Liouvillians
• Stability of time-periodic $\mathcal{P}\mathcal{T}$ and anti-$\mathcal{P}\mathcal{T}$-symmetric Hamiltonians with different periodicities
• Markovian to non-Markovian phase transition in the operator dynamics of a mobile impurity
• Dynamical non-Hermitian systems: Fingerprints and pure dephasing induced protection effect
• Non-Hermiticity induced thermal entanglement phase transition