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arXiv · 2211.14106

Real space circuit complexity as a probe of phase diagrams

Nishan C. Jayarama·Viktor Svensson
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Abstract

Circuit complexity has been used as a tool to study various properties in condensed matter systems, in particular as a way to probe the phase diagram. However, compared with measures based on entanglement, complexity has been found lacking. We show that when imposing penalty factors punishing non-locality, it becomes a much stronger probe of the phase diagram, able to probe more subtle features. We do this by deriving analytical solutions for the complexity in the XY chain with transverse field.

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Nishan C. Jayarama, Viktor Svensson. 2022-11-25. Real space circuit complexity as a probe of phase diagrams. https://doi.org/10.1103/physrevb.107.075122

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