SQUID-tunable microwave lumped-element oscillators and distributed resonators
ORAL
Abstract
We have fabricated lumped-element microwave oscillators and coplanar waveguide resonators consisting of a dc SQUID using submicron Al-AlOx-Al junctions with resonance frequencies in the range of several GHz. The SQUID oscillators consist of a dc SQUID shunted with a capacitor formed from superconducting layers. The CPW resonators are formed from Nb $\lambda $/2 coplanar transmission lines with a center conductor interrupted by an Al dc SQUID at the current anti-node of the fundamental mode. The resonance frequency can be varied by tuning the Josephson inductance of the SQUID with on-chip flux and bias-current lines. We discuss applications employing these devices, including a new readout scheme for superconducting flux qubits and for the detection of microwave cavity photons.
*Work supported by DARPA QuEST.
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