We present a direct measurement of the displacement noise spectrum of a macroscopic silicon flexure at room temperature. A cantilever attached to the 100 μm thick flexure holds a mirror which forms part of an optical cavity to enhance the displacement sensitivity to thermal noise. We predict the displacement noise spectrum using a simple model that assumes the dominant source of frequency-dependent loss is thermo-elastic damping and find good agreement with the experimental data. The measurement is consistent with a frequency-independent loss of combined with frequency-dependent thermo-elastic damping as the dominant losses. A crossover between the two that occurs well above the flexure resonant frequency allows a broadband measurement of the thermal noise of the silicon flexure. The flexure material, geometry, and measurement band are similar to those of planned future gravitational wave detectors.
Skip Nav Destination
Article navigation
9 January 2023
Research Article|
January 12 2023
Direct observation of the thermal noise spectrum of a silicon flexure membrane
Special Collection:
Gravitational Wave Detectors
D. P. Kapasi
;
D. P. Kapasi
a)
(Formal analysis, Validation, Visualization, Writing – original draft, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
a)Author to whom correspondence should be addressed: Disha.Kapasi@anu.edu.au
Search for other works by this author on:
T. T-H. Nguyen;
T. T-H. Nguyen
(Conceptualization, Data curation, Formal analysis, Investigation, Methodology)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
R. L. Ward
;
R. L. Ward
(Conceptualization, Funding acquisition, Investigation, Methodology, Supervision, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
J. Eichholz
;
J. Eichholz
(Supervision, Visualization, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
M. H. Iqbal;
M. H. Iqbal
(Investigation)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
T. G. McRae
;
T. G. McRae
(Supervision, Writing – original draft, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
P. A. Altin
;
P. A. Altin
(Investigation, Methodology, Supervision, Validation, Writing – original draft, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
D. E. McClelland
;
D. E. McClelland
(Conceptualization, Funding acquisition, Project administration, Resources, Supervision)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
B. J. J. Slagmolen
B. J. J. Slagmolen
(Conceptualization, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Validation, Writing – review & editing)
OzGrav-ANU, ARC Centre for Gravitational Astrophysics, College of Science, The Australian National University
, Canberra ACT 2601, Australia
Search for other works by this author on:
a)Author to whom correspondence should be addressed: Disha.Kapasi@anu.edu.au
Note: This paper is part of the APL Special Collection on Gravitational Wave Detectors.
Appl. Phys. Lett. 122, 022202 (2023)
Article history
Received:
October 25 2022
Accepted:
December 19 2022
Citation
D. P. Kapasi, T. T-H. Nguyen, R. L. Ward, J. Eichholz, M. H. Iqbal, T. G. McRae, P. A. Altin, D. E. McClelland, B. J. J. Slagmolen; Direct observation of the thermal noise spectrum of a silicon flexure membrane. Appl. Phys. Lett. 9 January 2023; 122 (2): 022202. https://doi.org/10.1063/5.0131984
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00