Capacity and quantum geometry of parametrized quantum circuits

  title={Capacity and quantum geometry of parametrized quantum circuits},
  author={Tobias Haug and Kishor Bharti and M. S. Kim},
To harness the potential of noisy intermediate-scale quantum devices, it is paramount to find the best type of circuits to run hybrid quantum-classical algorithms. Key candidates are parametrized quantum circuits that can be effectively implemented on current devices. Here, we evaluate the capacity and trainability of these circuits using the geometric structure of the parameter space via the effective quantum dimension, which reveals the expressive power of circuits in general as well as of… Expand
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