Amorphous silicon with extremely low absorption : beating thermal noise in gravitational astronomy

Birney, R. and Steinlechner, J. and Tornasi, Z. and MacFoy, S. and Vine, D. and Bell, A. S. and Gibson, D. and Hough, J. and Rowan, S. and Sortais, P. and Sproules, S. and Tait, S. and Martin, I. W. and Reid, S. (2018) Amorphous silicon with extremely low absorption : beating thermal noise in gravitational astronomy. Physical Review Letters, 121 (19). 191101. ISSN 1079-7114 (https://doi.org/10.1103/PhysRevLett.121.191101)

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Abstract

Amorphous silicon has ideal properties for many applications in fundamental research and industry. However, the optical absorption is often unacceptably high, particularly for gravitational wave detection. We report a novel ion beam deposition method for fabricating amorphous silicon with unprecedentedly low unpaired electron spin density and optical absorption; the spin-limit on absorption being surpassed for the first time. At low unpaired electron density, the absorption is no longer correlated with electron spins, but with the electronic mobility gap. Compared to standard ion beam deposition, the absorption at 1550 nm is lower by a factor of ≈100. This breakthrough shows that amorphous silicon could be exploited as an extreme performance optical coating in near-infra-red applications and it represents an important proof-of-concept for future gravitational wave detectors.

  • Item type:Article
    ID code:65794
    Dates:
    Date
    Event
    6 November 2018
    Published
    9 October 2018
    Accepted
    Notes:Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
    Subjects:Science > Physics
    Department:Faculty of Engineering > Biomedical Engineering
    Depositing user: Pure Administrator
    Date deposited:16 Oct 2018 09:46
    Last modified:26 Apr 2024 00:32
    Related URLs:
    URI:https://strathprints.strath.ac.uk/id/eprint/65794
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