Matchgate quantum computing and non-local process analysis

Autor(en)

Sven Ramelow, Alessandro Fedrizzi, Aephraim M. Steinberg, A.G. White

Abstrakt

In the circuit model, quantum computers rely on the availability of a universal quantum gate set. A particularly intriguing example is a set of two-qubit-only gates: 'matchgates', along with swap (the exchange of two qubits). In this paper, we show a simple decomposition of arbitrary matchgates into better-known elementary gates and implement a matchgate in a single-photon linear optics experiment. The gate performance is fully characterized via quantum process tomography. Moreover, we represent the resulting reconstructed quantum process in a novel way, as a fidelity map in the space of all possible non-local two-qubit unitaries. We propose the nonlocal distance-which is independent of local imperfections such as uncorrelated noise or uncompensated local rotations-as a new diagnostic process measure for the non-local properties of the implemented gate.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

University of Queensland, University of Toronto

Journal

New Journal of Physics

Band

12

Anzahl der Seiten

10

ISSN

1367-2630

DOI

https://doi.org/10.1088/1367-2630/12/8/083027

Publikationsdatum

2010

Peer-reviewed

Ja

ÖFOS 2012

103026 Quantenoptik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/1ecbbf5a-3eca-4a51-856a-71164b4f310d