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arXiv · 1303.6983

Quantum Catalysis of Magnetic Phase Transitions in a Quantum Simulator

Philip Richerme·Crystal Senko·Simcha Korenblit·Jacob Smith·Aaron Lee·Rajibul Islam·Wesley C. Campbell·Christopher Monroe
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Abstract

We control quantum fluctuations to create the ground state magnetic phases of a classical Ising model with a tunable longitudinal magnetic field using a system of 6 to 10 atomic ion spins. Due to the long-range Ising interactions, the various ground state spin configurations are separated by multiple first-order phase transitions, which in our zero temperature system cannot be driven by thermal fluctuations. We instead use a transverse magnetic field as a quantum catalyst to observe the first steps of the complete fractal devil's staircase, which emerges in the thermodynamic limit and can be mapped to a large number of many-body and energy-optimization problems.

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Philip Richerme, Crystal Senko, Simcha Korenblit, Jacob Smith, Aaron Lee, Rajibul Islam, Wesley C. Campbell, Christopher Monroe. 2013-03-27. Quantum Catalysis of Magnetic Phase Transitions in a Quantum Simulator. https://doi.org/10.1103/physrevlett.111.100506

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