TY  - JOUR
AU  - Mörstedt, Timm Fabian
AU  - Viitanen, Arto
AU  - Vadimov, Vasilii
AU  - Sevriuk, Vasilii
AU  - Partanen, Matti
AU  - Hyyppä, Eric
AU  - Catelani, Gianluigi
AU  - Silveri, Matti
AU  - Tan, Kuan Yen
AU  - Möttönen, Mikko
TI  - Recent Developments in Quantum‐Circuit Refrigeration
JO  - Annalen der Physik
VL  - 534
IS  - 7
SN  - 0003-3804
CY  - Leipzig
PB  - Barth
M1  - FZJ-2022-02200
SP  - 2100543
PY  - 2022
AB  - The recent progress in direct active cooling of the quantum-electric degrees of freedom in engineered circuits, or quantum-circuit refrigeration is reviewed. In 2017, the discovery of a quantum-circuit refrigerator (QCR) based on photon-assisted tunneling of quasiparticles through normal-metal–insulator–superconductor junctions inspired a series of experimental studies demonstrating the following main properties: i) the direct-current (dc) bias voltage of the junction can change the QCR-induced damping rate of a superconducting microwave resonator by orders of magnitude and give rise to nontrivial Lamb shifts, ii) the damping rate can be controlled in nanosecond time scales, and ii) the dc bias can be replaced by a microwave excitation, the amplitude of which controls the induced damping rate. Theoretically, it is predicted that state-of-the-art superconducting resonators and qubits can be reset with an infidelity lower than 10−4 in tens of nanoseconds using experimentally feasible parameters. A QCR-equipped resonator has also been demonstrated as an incoherent photon source with an output temperature above 1 K yet operating at millikelvin. This source has been used to calibrate cryogenic amplification chains. In the future, the QCR may be experimentally used to quickly reset superconducting qubits, and hence assist in the great challenge of building a practical quantum computer.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000796547200001
DO  - DOI:10.1002/andp.202100543
UR  - https://juser.fz-juelich.de/record/907771
ER  -