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Topological Atomic Spin Wave Lattices by Dissipative Couplings
Dongdong Hao1, Lin Wang1, Xingda Lu1
1Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University, Shanghai 200433, China.
Physical Review Letters
|April 28, 2023
Summary
Researchers engineered a dissipative Su-Schrieffer-Heeger (SSH) model using atomic spin waves, demonstrating topological edge modes in a novel dissipative gap. This work advances non-Hermitian topological quantum optics.
Area of Science:
- Quantum optics
- Condensed matter physics
- Topological physics
Background:
- Recent advances enable engineering of exotic lattice systems through dissipative couplings.
- Topological dissipation is a new frontier in quantum physics.
Purpose of the Study:
- To experimentally realize a dissipative version of the Su-Schrieffer-Heeger (SSH) model.
- To explore topological properties in a system with purely dissipative couplings.
Main Methods:
- Utilizing a spatial lattice of atomic spin waves in a vacuum vapor cell.
- Employing electromagnetically induced-transparency spectroscopy to construct the dissipation spectrum.
- Investigating edge modes within the dissipative gap.
Main Results:
- Experimental realization of a dissipative SSH model.
- Observation of topological edge modes within a dissipative gap.
- Validation of chiral symmetry in dissipative SSH couplings.
Conclusions:
- This study demonstrates a novel platform for non-Hermitian topological physics using dissipative couplings.
- The findings pave the way for realizing non-Hermitian topological quantum optics.
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