Matchgate quantum computing and non-local process analysis

Author(s): S. Ramelow, A. Fedrizzi, A. Steinberg, A. G. White

Journal: New J. Phys. 12 083027

Volume: 12

Year: 2010

DOI Number: 10.1088/1367-2630/12/8/083027

Link: Link to publication

Abstract:

In the circuit model, quantum computers rely on the availability of a universal quantum gate set. A particularly intriguing example of such a set is the “matchgates” along with swap, the simple exchange of two qubits. In this paper, we show a simple decomposition of arbitrary matchgates into better known elementary gates, and implement one matchgate in a linear optics experiment

using single photons. We characterize the gate performance via quantum process tomography and represent the resulting quantum process in a novel way, as a fidelity map in the space of all possible nonlocal two-qubit unitaries. In addition, we propose a new non-local, diagnostic process measure.

Note: http://arxiv.org/abs/0909.3016

File: Link to PDF