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arXiv · 1303.0874

A scanning transmon qubit for strong coupling circuit quantum electrodynamics

William E. Shanks·Devin L. Underwood·Andrew A. Houck
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Abstract

Like a quantum computer designed for a particular class of problems, a quantum simulator enables quantitative modeling of quantum systems that is computationally intractable with a classical computer. Quantum simulations of quantum many-body systems have been performed using ultracold atoms and trapped ions among other systems. Superconducting circuits have recently been investigated as an alternative system in which microwave photons confined to a lattice of coupled resonators act as the particles under study with qubits coupled to the resonators producing effective photon-photon interactions. Such a system promises insight into the nonequilibrium physics of interacting bosons but new tools are needed to understand this complex behavior. Here we demonstrate the operation of a scanning transmon qubit and propose its use as a local probe of photon number within a superconducting resonator lattice. We map the coupling strength of the qubit to a resonator on a separate chip and show that the system reaches the strong coupling regime over a wide scanning area.

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William E. Shanks, Devin L. Underwood, Andrew A. Houck. 2013-03-04. A scanning transmon qubit for strong coupling circuit quantum electrodynamics. https://doi.org/10.1038/ncomms2991

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