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arXiv · 2004.11945

Nonlinear effects on the dynamics of quantum harmonic modes coupled through angular momentum

N. Canosa·R. Rossignoli·Javier Garcia·Swapan Mandal·Kartick Chandra Saha
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Abstract

We investigate nonlinear effects on the dynamics of entanglement and other quantum observables in a system of two harmonic modes coupled through angular momentum. The nonlinearity arises from a quartic anharmonic term in each mode. The emergence and evolution of entanglement, non-gaussianity, photon number, photon antibunching and squeezing are examined for different initial product coherent states and couplings, through exact diagonalization in a truncated basis. It is shown that the anharmonic terms, even if weak, can lead to very significant effects for such initial states, considerably enhancing and stabilizing entanglement and leading to a non negligible non-gaussianity of the evolved states. They also affect other observables, stabilizing the dynamics after an initial transient regime, for not too small initial average populations of each mode. Analytic short-time approximate expressions are also provided.

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N. Canosa, R. Rossignoli, Javier Garcia, Swapan Mandal, Kartick Chandra Saha. 2020-04-24. Nonlinear effects on the dynamics of quantum harmonic modes coupled through angular momentum. https://doi.org/10.1088/1361-6455/abb3ad

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