Quantum-Squeezing-Induced Point-Gap Topology and Skin Effect

Abstract

We theoretically predict the squeezing-induced point-gap topology together with a {\it symmetry-protected ${\mathbb{Z}}_2$ skin effect} in a one-dimensional (1D) quadratic-bosonic system (QBS). Protected by a time-reversal symmetry, such a topology is associated with a novel ${\mathbb{Z}}_2$ invariant (similar to quantum spin-Hall insulators), which is fully capable of characterizing the occurrence of ${\mathbb{Z}}_2$ skin effect. Focusing on zero energy, the parameter regime of this skin effect in the phase diagram just corresponds to a {\it real-gap and point-gap coexisted topological phase}. Moreover, this phase associated with the {\it symmetry-protected ${\mathbb{Z}}_2$ skin effect} is experimentally observable by detecting the steady-state power spectral density. Our work is of fundamental interest in enriching non-Bloch topological physics by introducing quantum squeezing, and has potential applications for the engineering of symmetry-protected sensors based on the ${\mathbb{Z}}_2$ skin effect.

6 pages, 4 figures + Supplemental Material

References in corpus (12)

• Topological Acoustics
• Topological Origin of Non-Hermitian Skin Effects
• Efficient Light Funneling based on the non-Hermitian Skin Effect
• Edge Modes, Degeneracies, and Topological Numbers in Non-Hermitian Systems
• Weyl Exceptional Rings in a Three-Dimensional Dissipative Cold Atomic Gas
• Topological Transition in a Non-Hermitian Quantum Walk
• Periodic Table for Topological Bands with Non-Hermitian Bernard-LeClair Symmetries
• Squeezed Optomechanics with Phase-matched Amplification and Dissipation
• Observation of a dissipative phase transition in a one-dimensional circuit QED lattice
• Non-degenerate, three-wave mixing with the Josephson ring modulator
• Hermitian zero modes protected by nonnormality: Application of pseudospectra
• Complex modes in unstable quadratic bosonic forms