Loop State-preparation-and-measurement tomography of a two-qubit system

Autor: Feldman, M. E., Juul, G. K., Van Enk, S. J., Beck, M.
Rok vydání: 2018
Předmět:
Zdroj: J. Opt. Soc. Am B, Vol. 35, 1811-1816 (2018)
Druh dokumentu: Working Paper
DOI: 10.1364/JOSAB.35.001811
Popis: We experimentally demonstrate that loop state-preparation-and-measurement (SPAM) tomography is capable of detecting correlated errors in a two-qubit system. We prepare photon pairs in a state that approximates a Werner state, which may or may not be entangled. By performing measurements with multiple different detector settings we are able to detect correlated errors between two single-qubit measurements performed in different locations. No assumptions are made concerning either the state preparations or the measurements, other than that the dimensions of the states and the positive-operator-valued measures describing the detectors are known. The only other needed information is experimentally measured expectation values, which are analyzed for self-consistency. This demonstrates that loop SPAM tomography is a useful technique for detecting errors that would degrade the performance of multiple-qubit quantum information processors.
Comment: 6 pages, 3 figures. arXiv admin note: substantial text overlap with arXiv:1802.02526
Databáze: arXiv