Evidence of a critical phase transition in a purely temporal dynamics with long-delayed feedback

TL;DR

This paper demonstrates an absorbing phase transition in a purely temporal optical system with long-delayed feedback, showing critical phenomena akin to spatio-temporal dynamics, supported by experimental and numerical evidence.

Contribution

It provides experimental and numerical evidence of a critical phase transition in a purely temporal system, linking it to the directed percolation universality class.

Findings

Experimental evidence of a phase transition in a temporal optical system.

Numerical estimates of critical exponents match theoretical predictions.

Establishes a connection between temporal and spatio-temporal critical phenomena.

Abstract

Experimental evidence of an absorbing phase transition, so far associated with spatio-temporal dynamics is provided in a purely temporal optical system. A bistable semiconductor laser, with long-delayed opto-electronic feedback and multiplicative noise shows the peculiar features of a critical phenomenon belonging to the directed percolation universality class. The numerical study of a simple, effective model provides accurate estimates of the transition critical exponents, in agreement with both theory and our experiment. This result pushes forward an hard equivalence of non-trivial stochastic, long-delayed systems with spatio-temporal ones and opens a new avenue for studying out-of-equilibrium universality classes in purely temporal dynamics.