Fast tuning of superconducting microwave cavities
Paper in proceedings, 2008

Photons are fundamental excitations of electromagnetic fields and can be captured in cavities. For a given cavity with a certain size, the fundamental mode has a fixed frequency f which gives the photons a specific "color". The cavity also has a typical lifetime tau, which results in a finite linewidth delta f. If the size of the cavity is changed fast compared to tau, and so that the frequency change Delta f >> delta f, then it is possible to change the "color" of the captured photons. Here we demonstrate superconducting microwave cavities, with tunable effective lengths. The tuning is obtained by varying a Josephson inductance at one end of the cavity. We show data on four different samples and demonstrate tuning by several hundred linewidths in a time Delta t << tau. Working in the few photon limit, we show that photons stored in the cavity at one frequency will leak out from the cavity with the new frequency after the detuning. The characteristics of the measured devices make them suitable for different applications such as dynamic coupling of qubits and parametric amplification.

Author

Martin Sandberg

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Christopher Wilson

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Fredrik Persson

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Göran Johansson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Vitaly Shumeiko

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Thilo Bauch

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Per Delsing

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Proc. 2nd International Workshop on Solid-State Quantum Computing

12-21

Subject Categories

Physical Sciences

Condensed Matter Physics

ISBN

0094-243X978-0-7354-0605-6

More information

Created

10/8/2017