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arXiv · 1502.08015

Universal Control of an Oscillator with Dispersive Coupling to a Qubit

Stefan Krastanov·Victor V. Albert·Chao Shen·Chang-Ling Zou·Reinier W. Heeres·Brian Vlastakis·Robert J. Schoelkopf·Liang Jiang
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Abstract

We investigate quantum control of an oscillator mode off-resonantly coupled to an ancillary qubit. In the strong dispersive regime, we may drive the qubit conditioned on number states of the oscillator, which together with displacement operations can achieve universal control of the oscillator. Based on our proof of universal control, we provide explicit constructions for arbitrary state preparation and arbitrary unitary operation of the oscillator. Moreover, we present an efficient procedure to prepare the number state $\left|n\right\rangle$ using only $O\left(\sqrt{n}\right)$ operations. We also compare our scheme with known quantum control protocols for coupled qubit-oscillator systems. This universal control scheme of the oscillator can readily be implemented using superconducting circuits.

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Stefan Krastanov, Victor V. Albert, Chao Shen, Chang-Ling Zou, Reinier W. Heeres, Brian Vlastakis, Robert J. Schoelkopf, Liang Jiang. 2015-03-12. Universal Control of an Oscillator with Dispersive Coupling to a Qubit. https://doi.org/10.1103/physreva.92.040303

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