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arXiv · 0903.4028

Optimal Control of Superconducting N-level quantum systems

H. Jirari·F. W. J. Hekking·O. Buisson
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Abstract

We consider a current-biased dc SQUID in the presence of an applied time-dependent bias current or magnetic flux. The phase dynamics of such a Josephson device is equivalent to that of a quantum particle trapped in a $1-$D anharmonic potential, subject to external time-dependent control fields, {\it i.e.} a driven multilevel quantum system. The problem of finding the required time-dependent control field that will steer the system from a given initial state to a desired final state at a specified final time is formulated in the framework of optimal control theory. Using the spectral filter technique, we show that the selected optimal field which induces a coherent population transfer between quantum states is represented by a carrier signal having a constant frequency but which is time-varied both in amplitude and phase. The sensitivity of the optimal solution to parameter perturbations is also addressed.

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H. Jirari, F. W. J. Hekking, O. Buisson. 2009-03-24. Optimal Control of Superconducting N-level quantum systems. https://doi.org/10.1209/0295-5075/87/28004

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