Exceptional entanglement phenomena: non-Hermiticity meeting non-classicality

Abstract

Non-Hermitian (NH) extension of quantum-mechanical Hamiltonians represents one of the most significant advancements in physics. During the past two decades, numerous captivating NH phenomena have been revealed and demonstrated, but all of which can appear in both quantum and classical systems. This leads to the fundamental question: what NH signature presents a radical departure from classical physics? The solution of this problem is indispensable for exploring genuine NH quantum mechanics, but remains experimentally untouched so far. Here, we resolve this basic issue by unveiling distinct exceptional entanglement phenomena, exemplified by an entanglement transition, occurring at the exceptional point of NH interacting quantum systems. We illustrate and demonstrate such purely quantum-mechanical NH effects with a naturally dissipative light-matter system, engineered in a circuit quantum electrodynamics architecture. Our results lay the foundation for studies of genuinely quantum-mechanical NH physics, signified by exceptional-point-enabled entanglement behaviors.

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• Complex Extension of Quantum Mechanics
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Cited by in corpus (27)

• Non-Markovian Quantum Exceptional Points
• Entanglement Dynamics in Monitored Systems and the Role of Quantum Jumps
• Encircling the Liouvillian exceptional points: a brief review
• Measuring topological invariants for higher-order exceptional points in quantum three-mode systems
• Quantum entanglement and non-Hermiticity in free-fermion systems
• Experimental observation of non-Markovian quantum exceptional points
• Fate of non-Hermitian free fermions with Wannier-Stark ladder
• Waveguide QED with dissipative light-matter couplings
• Phase Transitions and Virtual Exceptional Points in Quantum Emitters Coupled to Dissipative Baths
• Non-Hermiticity in quantum nonlinear optics through symplectic transformations
• Nonadiabatic transitions in non-Hermitian $\mathcal{P}\mathcal{T}$-symmetric two-level systems
• Non-equilibrium dynamics of localization phase transition in the non-Hermitian Disorder-Aubry-André model
• Higher-order exceptional points in composite non-Hermitian systems
• Implementation and topological characterization of Weyl exceptional rings in quantum-mechanical systems
• Lindblad dynamics of open multi-mode bosonic systems: Algebra of bilinear superoperators, exceptional points and speed of evolution
• Robustness of entanglement in a non-Hermitian cavity-optomechanical system even away from exceptional points
• Dual opposing quadrature-PT symmetry
• Multimode Purcell Filter for Superconducting-Qubit Reset and Readout with Intrinsic Purcell Protection
• Multitype entanglement dynamics induced by exceptional points
• Characterization of non-Markovianity with maximal extractable qubit-reservoir entanglement
• An exceptional surface and its topology
• Entanglement generation across exceptional points in two-qubit open quantum system -- the role of initial states
• Enhancement of sensitivity near exceptional points in dissipative qubit-resonator systems
• Third-order exceptional surface in a pseudo-Hermitian superconducting circuit
• $\mathcal{P}\mathcal{T}$-Symmetric Spin--Boson Model with a Continuous Bosonic Spectrum: Exceptional Points and Dynamics
• Non-Hermitian topology in a single driven-dissipative Kerr-Cat qubit
• Non-Hermiticity induced thermal entanglement phase transition