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Title: Anti-Parity-Time Symmetric Optical Four-Wave Mixing in Cold Atoms
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.  more » « less
Award ID(s):
1806519 1741693
PAR ID:
10157690
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Physical review letters
Volume:
123
ISSN:
1092-0145
Page Range / eLocation ID:
193604
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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