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arXiv · 2008.00885

Experimentally verifying anti-Kibble-Zurek behavior in a quantum system under noisy control field

Ming-Zhong Ai·Jin-Ming Cui·Ran He·Zhong-Hua Qian·Xin-Xia Gao·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo
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Abstract

Kibble-Zurek mechanism (KZM) is a universal framework which could in principle describe phase transition phenomenon in any system with required symmetry properties. However, a conflicting observation termed anti-KZ behavior has been reported in the study of ferroelectric phase transition, in which slower driving results in more topological defects [S. M. Griffin, et al. Phys. Rev. X. 2, 041022 (2012)]. Although this research is significant, its experimental simulations have been scarce until now. In this work, we experimentally demonstrate anti-KZ behavior under noisy control field in three kinds of quantum phase transition protocols using a single trapped Yb ion. The density of defects is studied as a function of the quench time and the noise intensity. We experimentally verify that the optimal quench time to minimize excitation scales as a universal power law of the noise intensity. Our research sets a stage for quantum simulation of such anti-KZ behavior in two-level systems and reveals the limitations of the adiabatic protocols such as quantum annealing.

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Ming-Zhong Ai, Jin-Ming Cui, Ran He, Zhong-Hua Qian, Xin-Xia Gao, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo. 2020-08-03. Experimentally verifying anti-Kibble-Zurek behavior in a quantum system under noisy control field. https://doi.org/10.1103/physreva.103.012608

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