Speaker
Dr
Jeffrey Yen
(Stanford Physics)
Description
Phonon energy generated by an incident particle that scatters in a CDMS Si or Ge crystal gets absorbed by Transition Edge Sensors patterned on the surfaces of the crystals. These phonon sensors (TES/QETs) consist of overlapping thin films of superconducting aluminum and tungsten. Phonons created in the bulk of the detector propagate to the detector surfaces where they break Cooper pairs in the aluminum film and generate quasiparticles (qps). These qps diffuse and get trapped in the aluminum / tungsten overlap region of the sensors, where the energy band-gap is lower, before getting thermalized in the tungsten transition edge sensors and read-out as our signal.
Sensor thin-film quality and the width of the overlap region influence the overall phonon energy collection efficiency. In this poster, we present results from a series of precision x-ray experiments in which the width of the aluminum / tungsten overlap region was varied in a systematic manner. Our results are being fed into the design of SuperCDMS SNOLAB low-mass WIMP detectors.
Primary author
Dr
Jeffrey Yen
(Stanford Physics)
Co-authors
Ms
Astrid Tomada
(SLAC)
Prof.
Betty Young
(Santa Clara University)
Prof.
Blas Cabrera
(Stanford University)
Mr
Matt Cherry
(Stanford University)
Mr
Noah Kurinsky
(SLAC/Stanford)
Paul Brink
(SLAC)
Dr
Robert Moffatt
(Stanford University)
Mr
Trevor Howarth
(Stanford University)
