Quantum Signatures of Topological Phase in Bosonic Quadratic System

Abstract

Quantum entanglement and classical topology are two distinct phenomena that are difficult to be connected together. Here we discover that an open bosonic quadratic chain exhibits topology-induced entanglement effect. When the system is in the topological phase, the edge modes can be entangled in the steady state, while no entanglement appears in the trivial phase. This finding is verified through the covariance approach based on the quantum master equations, which provide exact numerical results without truncation process. We also obtain concise approximate analytical results through the quantum Langevin equations, which perfectly agree with the exact numerical results. We show the topological edge states exhibit near-zero eigenenergies located in the band gap and are separated from the bulk eigenenergies, which match the system-environment coupling (denoted by the dissipation rate) and thus the squeezing correlations can be enhanced. Our work reveals that the stationary entanglement can be a quantum signature of the topological phase in bosonic systems, and inversely the topological quadratic systems can be powerful platforms to generate robust entanglement.

14 pages, 7 figures

References in corpus (17)

• Supplementary information for "Quantum supremacy using a programmable superconducting processor"
• Topological Photonics
• Quantum computational advantage using photons
• Optomechanical entanglement between a movable mirror and a cavity field
• Strong quantum computational advantage using a superconducting quantum processor
• Nonlinear atom interferometer surpasses classical precision limit
• Nonlinear control of PT-symmetry and non-Hermitian topological states
• Deterministic entanglement generation from driving through quantum phase transitions
• Non-Hermitian chiral phononics through optomechanically-induced squeezing
• Coherent control of quantum topological states of light in Fock-state lattices
• Topology by Dissipation: Majorana Bosons in Metastable Quadratic Markovian Dynamics
• Observation of two-mode squeezing in a traveling wave parametric amplifier
• Einstein-Podolsky-Rosen experiment with two Bose-Einstein condensates
• Nonlinear interferometry beyond classical limit facilitated by cyclic dynamics
• Quantum-Squeezing-Induced Point-Gap Topology and Skin Effect
• Amplification of quantum signals by the non-Hermitian skin effect
• Dissipative Pairing Interactions: Quantum Instabilities, Topological Light, and Volume-Law Entanglement