By utilizing notions from statistical mechanics, we develop a general and selfconsistent theoretical framework capable of describing any weakly nonlinear optical multimode system involving conserved quantities. We derive the fundamental relations that govern the grand canonical ensemble through maximization of the Gibbs entropy at equilibrium. In this classical picture of statistical photomechanics, we obtain analytical expressions for the probability distribution, the grand partition function, and the relevant thermodynamic potentials. Our results universally apply to any other weakly nonlinear multimode bosonic system.
 Award ID(s):
 1839370
 NSFPAR ID:
 10392737
 Date Published:
 Journal Name:
 Journal of Physics A: Mathematical and Theoretical
 Volume:
 55
 Issue:
 29
 ISSN:
 17518113
 Page Range / eLocation ID:
 295002
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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