How long does it take to obtain a physical density matrix?
Quantum Physics
2015-12-23 v1
Abstract
The statistical nature of measurements alone easily causes unphysical estimates in quantum state tomography. We show that multinomial or Poissonian noise results in eigenvalue distributions converging to the Wigner semicircle distribution for already a modest number of qubits. This enables to specify the number of measurements necessary to avoid unphysical solutions as well as a new approach to obtain physical estimates.
Cite
@article{arxiv.1512.06866,
title = {How long does it take to obtain a physical density matrix?},
author = {Lukas Knips and Christian Schwemmer and Nico Klein and Jonas Reuter and Géza Tóth and Harald Weinfurter},
journal= {arXiv preprint arXiv:1512.06866},
year = {2015}
}
Comments
14 pages, 8 figures. Comments are welcome