Measuring complex-partition-function zeros of Ising models in quantum simulators

  title={Measuring complex-partition-function zeros of Ising models in quantum simulators},
  author={Abijith Krishnan and Markus Schmitt and Roderich Moessner and Markus Heyl},
  journal={Physical Review A},
Studying the zeros of partition functions in the space of complex control parameters allows one to understand formally how critical behavior of a many-body system can arise in the thermodynamic limit despite various no-go theorems for finite systems. In this work we propose protocols that can be realized in quantum simulators to measure the location of complex-partition-function zeros of classical Ising models. The protocols are solely based on the implementation of simple two-qubit gates… 

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