Anti-Parity-Time Symmetric Optical Four-Wave Mixing in Cold Atoms
Department
Physics
Document Type
Article
Publication Date
11-1-2019
Abstract
Non-Hermitian optical systems with parity-time (PT) symmetry have recently revealed many intriguing prospects that outperform conservative structures. The previous works are mostly rooted in complex arrangements with controlled gain-loss interplay. Here, we demonstrate anti-PT symmetry inherent in the nonlinear optical interaction based upon forward optical four-wave mixing in a laser-cooled atomic ensemble with negligible linear gain and loss. We observe that the pair of frequency modes undergo a nontrivial anti-PT phase transition between coherent power oscillation and optical parametric amplification in presence of a large phase mismatch.
Journal Title
Physical Review Letters
Journal ISSN
0031-9007,1079-7114
Volume
123
Issue
19
Digital Object Identifier (DOI)
10.1103/PhysRevLett.123.193604
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