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arXiv · 1711.00887

Probing quench dynamics across a quantum phase transition into a 2D Ising antiferromagnet

Elmer Guardado-Sanchez·Peter T. Brown·Debayan Mitra·Trithep Devakul·David A. Huse·Peter Schauss·Waseem S. Bakr
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Abstract

Simulating the real-time evolution of quantum spin systems far out of equilibrium poses a major theoretical challenge, especially in more than one dimension. We experimentally explore the dynamics of a two-dimensional Ising spin system with transverse and longitudinal fields as we quench it across a quantum phase transition from a paramagnet to an antiferromagnet. We realize the system with a near unit-occupancy atomic array of over 200 atoms obtained by loading a spin-polarized band insulator of fermionic lithium into an optical lattice and induce short-range interactions by direct excitation to a low-lying Rydberg state. Using site-resolved microscopy, we probe the correlations in the system after a sudden quench from the paramagnetic state and compare our measurements to exact calculations in the regime where it is possible. We achieve many-body states with longer-range antiferromagnetic correlations by implementing a near-adiabatic quench and study the buildup of correlations as we cross the quantum phase transition at different rates.

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Elmer Guardado-Sanchez, Peter T. Brown, Debayan Mitra, Trithep Devakul, David A. Huse, Peter Schauss, Waseem S. Bakr. 2017-11-02. Probing quench dynamics across a quantum phase transition into a 2D Ising antiferromagnet. https://doi.org/10.1103/physrevx.8.021069

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