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Title: Highly sensitive silicon crystal torque sensor operating at the thermal noise limit

Abstract

We describe a sensitive torque detector, based on a silicon single-crystal double-paddle oscillator (DPO). The high Q-factor ({approx}10{sup 5} at room temperature and in vacuum) makes DPOs well suited for the detection of weak forces. The limiting sensitivity of a sensor is given by Brownian (thermal) noise if all external disturbances are eliminated. In this case, the minimum detectable force can be decreased by measuring over a time significantly longer than the oscillator's relaxation time. We demonstrate operation in this regime, with integration times of up to 14 h. A resulting torque sensitivity of 2x10{sup -18} N m is reached. Tests are performed to show that the sensor is only affected by thermal noise. The present sensor is well suited for measurements of extremely weak forces, e.g., of gravitational attraction between laboratory masses.

Authors:
; ;  [1]
  1. Institut fuer Experimentalphysik, Heinrich-Heine-Universitaet Duesseldorf, Universitaetsstrasse 1, 40225 Duesseldorf (Germany)
Publication Date:
OSTI Identifier:
20953266
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 2; Other Information: DOI: 10.1063/1.2437133; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; DETECTION; DISTURBANCES; MONOCRYSTALS; NOISE; OSCILLATORS; RELAXATION TIME; SEMICONDUCTOR DEVICES; SEMICONDUCTOR MATERIALS; SENSITIVITY; SILICON; TEMPERATURE RANGE 0273-0400 K; TORQUE

Citation Formats

Haiberger, L., Weingran, M., and Schiller, S. Highly sensitive silicon crystal torque sensor operating at the thermal noise limit. United States: N. p., 2007. Web. doi:10.1063/1.2437133.
Haiberger, L., Weingran, M., & Schiller, S. Highly sensitive silicon crystal torque sensor operating at the thermal noise limit. United States. doi:10.1063/1.2437133.
Haiberger, L., Weingran, M., and Schiller, S. Thu . "Highly sensitive silicon crystal torque sensor operating at the thermal noise limit". United States. doi:10.1063/1.2437133.
@article{osti_20953266,
title = {Highly sensitive silicon crystal torque sensor operating at the thermal noise limit},
author = {Haiberger, L. and Weingran, M. and Schiller, S.},
abstractNote = {We describe a sensitive torque detector, based on a silicon single-crystal double-paddle oscillator (DPO). The high Q-factor ({approx}10{sup 5} at room temperature and in vacuum) makes DPOs well suited for the detection of weak forces. The limiting sensitivity of a sensor is given by Brownian (thermal) noise if all external disturbances are eliminated. In this case, the minimum detectable force can be decreased by measuring over a time significantly longer than the oscillator's relaxation time. We demonstrate operation in this regime, with integration times of up to 14 h. A resulting torque sensitivity of 2x10{sup -18} N m is reached. Tests are performed to show that the sensor is only affected by thermal noise. The present sensor is well suited for measurements of extremely weak forces, e.g., of gravitational attraction between laboratory masses.},
doi = {10.1063/1.2437133},
journal = {Review of Scientific Instruments},
number = 2,
volume = 78,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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