Highly Controllable Qubit-Bath Coupling Based on a Sequence of Resonators
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.
KeywordsQuantum bit Open quantum system Environment engineering Circuit quantum electrodynamics
We acknowledge the Väisälä Foundation and the Finnish National Doctoral Programme in Materials Physics (NGSMP) for financial support. This research has been supported by the Academy of Finland through its Centres of Excellence Program under Grant No. 251748 (COMP) in addition to the Grants No. 138903 and No. 135794. We have received funding from the European Research Council under Starting Independent Researcher Grant No. 278117 (SINGLEOUT).