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Quantum capacitance detector (QCD)

Quantum capacitance detector (QCD) Project Logo

Project led by Dr. Pierre Echternach in JPL Division 38.

The QCD is the most sensitive far-IR detector ever made. Photons break Cooper pairs in a superconducting absorber, and tunnel in and out of the capacitive element of a resonator, creating frequency shifts that are detected with an RF / microwave probe tone. The QCD has demonstrated both very low noise equivalent power (NEP below 10^-20 W/sqrt(Hz)) and individual far-IR photon counting.

QCD References:


Photo of Charles Bradford
Charles Bradford
Interstellar and Heliospheric Physics