Experimental comparison of efficient tomography schemes for a six-qubit state.

  title={Experimental comparison of efficient tomography schemes for a six-qubit state.},
  author={Christian Schwemmer and G{\'e}za T{\'o}th and Alexander Niggebaum and Tobias Moroder and David Gross and Otfried G{\"u}hne and Harald Weinfurter},
  journal={Physical review letters},
  volume={113 4},
Quantum state tomography suffers from the measurement effort increasing exponentially with the number of qubits. Here, we demonstrate permutationally invariant tomography for which, contrary to conventional tomography, all resources scale polynomially with the number of qubits both in terms of the measurement effort as well as the computational power needed to process and store the recorded data. We demonstrate the benefits of combining permutationally invariant tomography with compressed… 

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