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arXiv · 1612.06902

Direct observation of dynamical quantum phase transitions in an interacting many-body system

P. Jurcevic·H. Shen·P. Hauke·C. Maier·T. Brydges·C. Hempel·B. P. Lanyon·M. Heyl·R. Blatt·C. F. Roos
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Abstract

Dynamical quantum phase transitions (DQPTs) extend the concept of phase transitions and thus universality to the non-equilibrium regime. In this letter, we investigate DQPTs in a string of ions simulating interacting transverse-field Ising models. We observe non-equilibrium dynamics induced by a quantum quench and show for strings of up to 10 ions the direct detection of DQPTs by measuring a quantity that becomes non-analytic in time in the thermodynamic limit. Moreover, we provide a link between DQPTs and the dynamics of other relevant quantities such as the magnetization, and we establish a connection between DQPTs and entanglement production.

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P. Jurcevic, H. Shen, P. Hauke, C. Maier, T. Brydges, C. Hempel, B. P. Lanyon, M. Heyl, R. Blatt, C. F. Roos. 2016-12-20. Direct observation of dynamical quantum phase transitions in an interacting many-body system. https://doi.org/10.1103/physrevlett.119.080501

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