A quasiparticle-trap-assisted transition-edge sensor for phonon-mediated particle detection

Journal Article · Wed Nov 01 04:00:00 EST 1995 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1146105· OSTI ID:124855

Irwin, K D; Nam, S W; Cabrera, B; Chugg, B ^[1]; Young, B A ^[2]

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1. Department of Physics, Stanford University, Stanford, California 94305-4060 (United States)
2. Department of Physics, Santa Clara University, Santa Clara, California 95053 (United States)

We have demonstrated the operation of composite superconducting tungsten and aluminum transition-edge sensors which take advantage of quasiparticle trapping and electrothermal feedback. We call these devices W/Al QETs (quasiparticle-trap-assisted electrothermal feedback transition-edge sensors). The quasiparticle trapping mechanism makes it possible to instrument large surface areas without increasing sensor heat capacity, thus allowing larger absorbers and reducing phonon collection times. The sensor consists of a 30-nm-thick superconducting tungsten thin film with {ital T}{sub {ital c}}{similar_to}80 mK deposited on a high-purity silicon substrate. The W film is patterned into 200 parallel lines segments, each 2 {mu}m wide and 800 {mu}m long. Eight superconducting aluminum thin film pads are electrically connected to each segment, and cover a much larger surface area than the W. When phonons from particle interactions in the silicon crystal impinge on an aluminum pad, Cooper pairs are broken, forming quasiparticles which diffuse to the tungsten lines where they are rapidly thermalized. The W film is voltage biased, and self-regulates in temperature within its superconducting transition region by electrothermal feedback. Heat deposited in the film causes a current pulse of {similar_to}100 {mu}s duration, which is measured with a series array of dc superconducting quantum interference devices. We have demonstrated an energy resolution of {lt}350 eV full width at half-maximum for 6 keV x rays incident on the backside of a 1 cm{times}1 cm{times}1 mm (0.25 g) silicon absorber, the highest resolution that has been reported for a fast ({lt}1 ms pulse duration) calorimetric detector with an absorber mass{gt}0.1 g. Applications of this technology include dark matter searches and neutrino detection. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

• OSTI ID: 124855
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 11 Vol. 66; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
ALUMINIUM
ENERGY RESOLUTION
KEV RANGE 01-10
QUASI PARTICLES
RADIATION DETECTORS
SUPERCONDUCTING FILMS
TRAPPING
TUNGSTEN
X RADIATION