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Efficient error characterization in Quantum Information Processing

Benjamin Lévi·Cecilia C. López·Joseph Emerson·D. G. Cory
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Abstract

We describe how to use the fidelity decay as a tool to characterize the errors affecting a quantum information processor through a noise generator $G_{\tau}$. For weak noise, the initial decay rate of the fidelity proves to be a simple way to measure the magnitude of the different terms in $G_{\tau}$. When the generator has only terms associated with few-body couplings, our proposal is scalable. We present the explicit protocol for estimating the magnitude of the noise generators when the noise consists of only one and two-body terms, and describe a method for measuring the parameters of more general noise models. The protocol focuses on obtaining the magnitude with which these terms affect the system during a time step of length $\tau$; measurement of this information has critical implications for assesing the scalability of fault-tolerant quantum computation in any physical setup.

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Benjamin Lévi, Cecilia C. López, Joseph Emerson, D. G. Cory. 2006-08-31. Efficient error characterization in Quantum Information Processing. https://doi.org/10.1103/physreva.75.022314

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