TY - JOUR AU - Hsu, Hao AU - Silveri, Matti AU - Gunyhó, András AU - Goetz, Jan AU - Catelani, Gianluigi AU - Möttönen, Mikko TI - Tunable refrigerator for nonlinear quantum electric circuits JO - Physical review / B VL - 101 IS - 23 SN - 2469-9950 CY - Woodbury, NY PB - Inst. M1 - FZJ-2020-02296 SP - 235422 PY - 2020 AB - The emerging quantum technological applications call for fast and accurate initialization of the corresponding devices to low-entropy quantum states. To this end, we theoretically study a recently demonstrated quantum-circuit refrigerator in the case of nonlinear quantum electric circuits such as superconducting qubits. The maximum refrigeration rate of transmon and flux qubits is observed to be roughly an order of magnitude higher than that of usual linear resonators, increasing flexibility in the design. We find that for typical experimental parameters, the refrigerator is suitable for resetting different qubit types to fidelities above 99.99% in a few or a few tens of nanoseconds depending on the scenario. Thus the refrigerator appears to be a promising tool for quantum technology and for detailed studies of open quantum systems. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000539494900008 DO - DOI:10.1103/PhysRevB.101.235422 UR - https://juser.fz-juelich.de/record/877571 ER -