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arXiv · 1304.4829

Highly Controllable Qubit-Bath Coupling Based on a Sequence of Resonators

P. J. Jones·J. Salmilehto·M. Möttönen
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Abstract

Combating the detrimental effects of noise remains a major challenge in realizing a scalable quantum computer. To help to address this challenge, we introduce a model realizing a controllable qubit-bath coupling using a sequence of LC resonators. The model establishes a strong coupling to a low-temperature environment which enables us to lower the effective qubit temperature making ground state initialization more efficient. The operating principle is similar to that of a recently proposed coplanar-waveguide cavity (CPW) system, for which our work introduces a complementary and convenient experimental realization. The lumped-element model utilized here provides an easily accessible theoretical description. We present analytical solutions for some experimentally feasible parameter regimes and study the control mechanism. Finally, we introduce a mapping between our model and the recent CPW system.

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P. J. Jones, J. Salmilehto, M. Möttönen. 2013-09-27. Highly Controllable Qubit-Bath Coupling Based on a Sequence of Resonators. https://doi.org/10.1007/s10909-013-0889-3

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