Physical model of continuous two-qubit parity measurement in a cavity-QED network
We propose and analyze a physical implementation of two-qubit parity measurements as required for continuous error correction, assuming a setup in which the individual qubits are strongly coupled to separate optical cavities. A single optical probe beam scatters sequentially from the two cavities, and the continuous parity measurement is realized via fixed quadrature homodyne photodetection. We present models based on quantum stochastic differential equations (QSDEs) for both an ideal continuous parity measurement and our proposed cavity quantum electrodynamics (cavity QED) implementation; a recent adiabatic elimination theorem for QSDEs is used to assert strong convergence of the latter to the former in an appropriate limit of physical parameters. Performance of the cavity QED scheme is studied via numerical simulation with experimentally realistic parameters.
Additional Information© 2009 The American Physical Society. Received 5 December 2008; published 9 February 2009. This research is supported by the ARO under Grant No. W911NF-06-1-0378, by the ONR under Grant No. N00014- 05-1-0420, and by an HP Labs Innovation Research Grant. PACS number(s): 03.67.Pp, 42.50.Lc, 42.50.Pq, 03.65.Yz.
Published - Kerckhoff2009p4418Phys_Rev_A.pdf