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arXiv · 1301.5534

Quantum simulation of Kibble-Zurek mechanism with a semiconductor electron charge qubit

Cheng Zhou·Li Wang·Tao Tu·Hai-Ou Li·Guang-Can Guo·Hong-Wen Jiang·Guo-Ping Guo
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Abstract

The Kibble-Zurek mechanism provides a description of the topological structure occurring in the symmetry breaking phase transitions, which may manifest as the cosmological strings in the early universe or vortex lines in the superfulid. A particularly intriguing analogy between Kibble-Zurek mechanism and a text book quantum phenomenon, Landau-Zener transition has been discovered, but is difficult to observe up to now. In recent years, there has been broad interest in quantum simulations using different well-controlled physical setups, in which full tunability allows access to unexplored parameter regimes. Here we demonstrate a proof-of-principle quantum simulation of Kibble-Zurek mechanism using a single electron charge qubit in double quantum dot, set to behave as Landau-Zener dynamics. We measure the qubit states as a function of driven pulse velocity and successfully reproduce Kibble-Zurek like dependence of topological defect density on the quench rate. The high-level controllability of semiconductor two-level system make it a platform to test the key elements of topological defect formation process and shed a new insight on the aspect of non-equilibrium phase transitions.

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Cheng Zhou, Li Wang, Tao Tu, Hai-Ou Li, Guang-Can Guo, Hong-Wen Jiang, Guo-Ping Guo. 2013-01-23. Quantum simulation of Kibble-Zurek mechanism with a semiconductor electron charge qubit. https://doi.org/10.1103/physreva.89.022337

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