Kinetic Inductance Detectors

Lowitz_thesis_KID
Kinetic Inductance Detector fabricated by Timbie group alumna, Dr. Amy Lowitz

The Kinetic Inductance Detector (KID) is superconducting detector with the potential to revolutionize astronomy at sub-millimeter frequencies, and beyond.  KIDs are extremely sensitive at a wide range of incident optical loads, and are relatively simple to fabricate into large arrays, making them ideal detectors for use in the next generation of sub-mm and CMB telescopes.  Furthermore, individual detectors are highly tunable, making KID arrays sensitive to a wide range of applications for a single telescope.

A KID are formatted as a collection of microresonator circuits connected to a common feedline, where each resonator can be modeled as an RLC circuit tuned to a particular resonance frequency.  When illuminated, incident photons break Cooper pairs, changing the impedance of the given detector, i.e. the Kinetic Inductance Effect.  The resulting impedance changes the resonant frequency and quality factor of the given detector.  Each resonance in the array can be individually analyzed by a common readout system, which can be used to infer the incident optical loading.

 

KID schematic
Summary of KID operation, from Day (2013)

The Timbie Group has expertise in a wide range of KID applications, ranging from CMB to the intensity mapping of CO/CII.  The group is currently working closely with NASA-GSFC, with whom we are leading the modeling effort for the EXCLAIM detectors.  We are also working to improve on KID modeling for future applications, including the next generations of ground-, air-, and space-based telescopes.