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arXiv · 1310.6448

Tomography via Correlation of Noisy Measurement Records

Colm A. Ryan·Blake R. Johnson·Jay M. Gambetta·Jerry M. Chow·Marcus P. da Silva·Oliver E. Dial·Thomas A. Ohki
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Abstract

We present methods and results of shot-by-shot correlation of noisy measurements to extract entangled state and process tomography in a superconducting qubit architecture. We show that averaging continuous values, rather than counting discrete thresholded values, is a valid tomographic strategy and is in fact the better choice in the low signal-to-noise regime. We show that the effort to measure $N$-body correlations from individual measurements scales exponentially with $N$, but with sufficient signal-to-noise the approach remains viable for few-body correlations. We provide a new protocol to optimally account for the transient behavior of pulsed measurements. Despite single-shot measurement fidelity that is less than perfect, we demonstrate appropriate processing to extract and verify entangled states and processes.

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Colm A. Ryan, Blake R. Johnson, Jay M. Gambetta, Jerry M. Chow, Marcus P. da Silva, Oliver E. Dial, Thomas A. Ohki. 2013-12-20. Tomography via Correlation of Noisy Measurement Records. https://doi.org/10.1103/physreva.91.022118

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