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arXiv · 1903.02145

Experimentally testing quantum critical dynamics beyond the Kibble-Zurek mechanism

Jin-Ming Cui·Fernando Javier Gómez-Ruiz·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo·Adolfo del Campo
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Abstract

We experimentally probe the distribution of kink pairs resulting from driving a one-dimensional quantum Ising chain through the paramagnet-ferromagnet quantum phase transition, using a single trapped ion as a quantum simulator in momentum space. The number of kink pairs after the transition follows a Poisson binomial distribution, in which all cumulants scale with a universal power-law as a function of the quench time in which the transition is crossed. We experimentally verified this scaling for the first cumulants and report deviations due to noise-induced dephasing of the trapped ion. Our results establish that the universal character of the critical dynamics can be extended beyond the paradigmatic Kibble-Zurek mechanism, which accounts for the mean kink number, to characterize the full probability distribution of topological defects.

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Jin-Ming Cui, Fernando Javier Gómez-Ruiz, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo, Adolfo del Campo. 2019-03-06. Experimentally testing quantum critical dynamics beyond the Kibble-Zurek mechanism. https://doi.org/10.1038/s42005-020-0306-6

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