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Published on: June 28, 2018
Non-Hermitian topological superfluidity in a three-dimensional Fermi gas with spin-orbit coupling
Pingcheng Zhu1,2, Lihong Zhou1,2, Jianxin Zhong1,2
1Institute for Quantum Science and Technology, Shanghai University, Shanghai 200444, China.
Iscience
|July 28, 2026
Summary
Artificial spin-orbit coupling (SOC) and dissipation in ultracold Fermi gases create novel superfluid and topological phases. This research explores how these factors influence pairing behavior and stability in quantum systems.
Area of Science:
- Quantum many-body physics
- Ultracold atomic gases
- Condensed matter theory
Background:
- Artificial spin-orbit coupling (SOC) and non-Hermitian potentials are experimentally realized in ultracold atoms.
- These systems offer a platform to study the interplay between dissipation and SOC in quantum many-body systems.
Purpose of the Study:
- Investigate the pairing behavior of a two-component Fermi gas in a 3D cubic lattice with Rashba SOC and complex-valued interactions.
- Elucidate the interplay of dissipation and SOC in Fermi gas pairing.
Main Methods:
- Non-Hermitian mean-field theory applied to a two-component Fermi gas.
- Analysis of phase transitions, reentrant superfluidity, and stability regions.
Main Results:
- Dissipation drives superfluid-to-normal phase transitions and induces reentrant superfluidity.
- SOC and dissipation synergistically expand stability regions for normal and metastable superfluid phases.
- A Zeeman field induces a topological superfluid phase with a nontrivial topological invariant.
Conclusions:
- The study reveals a rich spectrum of pairing phenomena in dissipative quantum systems.
- Highlights the significant role of dissipation and SOC in controlling quantum phase behavior.
- Demonstrates the potential for creating topological phases in engineered quantum systems.
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