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Solitons in quantum nonlinear optics

R. Y. Chiao, Ivan Deutsch, J. C. Garrison, Ewan M. Wright

Published Jul 16, 2021• 1 citation

Abstract

Alkali vapors excited by light near resonance are known to possess very large nonlinear optical coefficients n 2 , which can have either sign depending on the sign of the detuning. Spatial solitons in a Fabry-Perot resonator filled with such vapors can result from these nonlinearities. The nonlinear Schrodinger equation (NLS) obeyed by these solitons is formally equivalent to a nonrelativistic many-body field theory, in which photons behave like nonrelativistic bosons with pairwise interactions. When n 2 is positive, these interactions are attractive; when is negative, they are repulsive. With n 2 positive, it is predicted that a self-trapped, 1D spatial soliton (the hyperbolic secant solution to the ID NLS) should be observable, and we plan to perform soliton-soliton collision experiments with such solitons. At the quantum level, the light inside such a soliton should be self-squeezed, and we plan to observe this using the Shirasaki-Haus method. The possibility of observing the two-photon bound state, the diphoton, will be explored. With n 2 negative, a ID spatial dark soliton with antibunching of photons should result. Moreover, with n 2 negative, a 2D vortex soliton should form, and we plan to examine the dynamics of these photonic vortices at both classical and quantum levels. The possibility that these vortices obey anyonic statistics will be explored. These optical systems thus constitute an experimentally accessible arena in which many-body phenomena analogous to those in condensed matter physics, especially topological ones, such as the Kosterlitz-Thouless phase transition, superfluidity, and anyonic statistics, may be observed.

DOI: 10.1201/9781003209638-9

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