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arXiv · 1208.2441

Direct Wigner tomography of a superconducting anharmonic oscillator

Yoni Shalibo·Roy Resh·Ofer Fogel·David Shwa·Radoslaw Bialczak·John M. Martinis·Nadav Katz
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Abstract

The analysis of wave-packet dynamics may be greatly simplified when viewed in phase-space. While harmonic oscillators are often used as a convenient platform to study wave-packets, arbitrary state preparation in these systems is more challenging. Here, we demonstrate a direct measurement of the Wigner distribution of complex photon states in an anharmonic oscillator - a superconducting phase circuit, biased in the small anharmonicity regime. We test our method on both non-classical states composed of two energy eigenstates and on the dynamics of a phase-locked wavepacket. This method requires a simple calibration, and is easily applicable in our system out to the fifth level.

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Yoni Shalibo, Roy Resh, Ofer Fogel, David Shwa, Radoslaw Bialczak, John M. Martinis, Nadav Katz. 2012-08-12. Direct Wigner tomography of a superconducting anharmonic oscillator. https://doi.org/10.1103/physrevlett.110.100404

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