Scalable two- and four-qubit parity measurement with a threshold photon counter
Abstract
Parity measurement is a central tool to many quantum information processing tasks. In this Letter, we propose a method to directly measure two- and four-qubit parity with low overhead in hard- and software, while remaining robust to experimental imperfections. Our scheme relies on dispersive qubit-cavity coupling and photon counting that is sensitive only to intensity; both ingredients are widely realized in many different quantum computing modalities. For a leading technology in quantum computing, superconducting integrated circuits, we analyze the measurement contrast and the back action of the scheme and show that this measurement comes close enough to an ideal parity measurement to be applicable to quantum error correction.
Cite
@article{arxiv.1502.03340,
title = {Scalable two- and four-qubit parity measurement with a threshold photon counter},
author = {Luke C. G. Govia and Emily J. Pritchett and B. L. T. Plourde and Maxim G. Vavilov and R. McDermott and Frank K. Wilhelm},
journal= {arXiv preprint arXiv:1502.03340},
year = {2015}
}
Comments
5 pages + 7 pages supplementary, 4 figures + 2 figures supplementary