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arXiv · 0902.4194

The Quantum Capacitance Detector: A concept for a pair-breaking radiation detector based on the single Cooper-pair box

M. D. Shaw·J. Bueno·P. Day·C. M. Bradford·P. M. Echternach
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Abstract

We present a proposed design for a pair-breaking photodetector for far-infrared and sub-millimeter radiation. Antenna-coupled radiation generates quasiparticles in a superconducting absorber, the density of which are measured using a single Cooper-pair box. Readout is performed using an electromagnetic oscillator or a microwave resonator, which is well suited for frequency multiplexing in large arrays. Theoretical limits to detector sensitivity are discussed and modeled, with predicted sensitivities rivaling transition-edge sensors and microwave kinetic inductance detectors. We anticipate that this detector can be used to address key scientific goals in far-infrared and sub-millimeter astronomy.

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M. D. Shaw, J. Bueno, P. Day, C. M. Bradford, P. M. Echternach. 2009-03-13. The Quantum Capacitance Detector: A concept for a pair-breaking radiation detector based on the single Cooper-pair box. https://doi.org/10.1103/physrevb.79.144511

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