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Title: A strained silicon cold electron bolometer using Schottky contacts

We describe optical characterisation of a strained silicon cold electron bolometer (CEB), operating on a 350 mK stage, designed for absorption of millimetre-wave radiation. The silicon cold electron bolometer utilises Schottky contacts between a superconductor and an n{sup ++} doped silicon island to detect changes in the temperature of the charge carriers in the silicon, due to variations in absorbed radiation. By using strained silicon as the absorber, we decrease the electron-phonon coupling in the device and increase the responsivity to incoming power. The strained silicon absorber is coupled to a planar aluminium twin-slot antenna designed to couple to 160 GHz and that serves as the superconducting contacts. From the measured optical responsivity and spectral response, we calculate a maximum optical efficiency of 50% for radiation coupled into the device by the planar antenna and an overall noise equivalent power, referred to absorbed optical power, of 1.1×10{sup −16} W Hz{sup −1/2} when the detector is observing a 300 K source through a 4 K throughput limiting aperture. Even though this optical system is not optimized, we measure a system noise equivalent temperature difference of 6 mK Hz{sup −1/2}. We measure the noise of the device using a cross-correlation of time stream data, measured simultaneously with two junctionmore » field-effect transistor amplifiers, with a base correlated noise level of 300 pV Hz{sup −1/2} and find that the total noise is consistent with a combination of photon noise, current shot noise, and electron-phonon thermal noise.« less
Authors:
; ; ; ; ;  [1] ; ; ; ; ;  [2] ;  [3] ;  [1] ;  [4]
  1. School of Physics and Astronomy, Cardiff University, Queen's Buildings, The Parade, Cardiff CF24 3AA (United Kingdom)
  2. Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)
  3. VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT Espoo (Finland)
  4. (United States)
Publication Date:
OSTI Identifier:
22311229
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; ALUMINIUM; APERTURES; BOLOMETERS; CHARGE CARRIERS; DOPED MATERIALS; ELECTRIC CONTACTS; ELECTRON-PHONON COUPLING; ELECTRONS; FIELD EFFECT TRANSISTORS; NOISE; OPTICAL PROPERTIES; OPTICAL SYSTEMS; PHONONS; SEMICONDUCTOR JUNCTIONS; SILICON; SPECTRAL RESPONSE; STRAINS