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arXiv · 1306.4989

Dynamical symmetry breaking with optimal control: reducing the number of pieces

Matthew J. M. Power·Gabriele De Chiara
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Abstract

We analyse the production of defects during the dynamical crossing of a mean-field phase transition with a real order parameter. When the parameter that brings the system across the critical point changes in time according to a power-law schedule, we recover the predictions dictated by the well-known Kibble-Zurek theory. For a fixed duration of the evolution, we show that the average number of defects can be drastically reduced for a very large but finite system, by optimising the time dependence of the driving using optimal control techniques. Furthermore, the optimised protocol is robust against small fluctuations.

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Matthew J. M. Power, Gabriele De Chiara. 2013-06-20. Dynamical symmetry breaking with optimal control: reducing the number of pieces. https://doi.org/10.1103/physrevb.88.214106

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