Developing an optical chopper-modulated capacitive probe for measuring surface charge

Details Developing an optical chopper-modulated capacitive probe for measuring surface charge Developing an optical chopper-modulated capacitive probe for measuring surface charge

Apr 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007rsci...78d6102u&link_type=abstract

Review of Scientific Instruments, Volume 78, Issue 4, pp. 046102-046102-3 (2007).

Physics

Optics

4

Astrometric And Interferometric Instruments, Sensors, Remote Sensing, Interferometry

Scientific paper

Gravitational-wave observatories such as Laser Interferometer Gravitational-Wave Observatory (LIGO) use suspended optics in a Michelson interferometer configuration to measure strains in space between 10 Hz and 3 kHz. One potential noise source in this frequency range is the buildup and motion of surface charge on the optics, which can generate fluctuating electric fields, interfere with position control, and reduce reflectance by attracting dust to the optical surface. We have developed a capacitive probe to measure the magnitude and relaxation time of surface charge deposited on smaller test optics in high vacuum (~10-5 Torr). Our device modulates capacitance with a tuning-fork optical chopper between probe and sample, chosen for vacuum compatibility and minimal cost. We have found that the probe has a resolution of (3.5+/-0.5)×105 e-/cm2 in air, on the order of charging levels that could contribute noise to Advanced LIGO, and sufficient for measuring relaxation times on test optics.

Affiliated with

Also associated with

No associations

Rating

Developing an optical chopper-modulated capacitive probe for measuring surface charge does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Developing an optical chopper-modulated capacitive probe for measuring surface charge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Developing an optical chopper-modulated capacitive probe for measuring surface charge will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1360581