Quantum noise reduction using squeezed states in LIGO
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2013.
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | eng |
| Published: |
Massachusetts Institute of Technology
2013
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/1721.1/79427 |
| _version_ | 1811078584757911552 |
|---|---|
| author | Dwyer, Sheila E. (Sheila Elizabeth) |
| author2 | Nergis Mavalvala. |
| author_facet | Nergis Mavalvala. Dwyer, Sheila E. (Sheila Elizabeth) |
| author_sort | Dwyer, Sheila E. (Sheila Elizabeth) |
| collection | MIT |
| description | Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2013. |
| first_indexed | 2024-09-23T11:02:36Z |
| format | Thesis |
| id | mit-1721.1/79427 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T11:02:36Z |
| publishDate | 2013 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/794272019-04-10T12:09:42Z Quantum noise reduction using squeezed states in LIGO Sensitivity improvement of a LIGO gravitational Wayne detector through squeezed state injection Dwyer, Sheila E. (Sheila Elizabeth) Nergis Mavalvala. Massachusetts Institute of Technology. Department of Physics. Massachusetts Institute of Technology. Department of Physics. Physics. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2013. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Title as it appears in MIT Commencement Exercises program, June 2013: Sensitivity improvement of a LIGO gravitational Wayne detector through squeezed state injection. Cataloged from student-submitted PDF version of thesis. Includes bibliographical references (p. 217-223). Direct detection of gravitational waves will require earth based detectors to measure strains of the order 10-21, at frequencies of 100 Hz, a sensitivity that has been accomplished with the initial generation of LIGO interferometric gravitational wave detectors. A new generation of detectors currently under construction is designed improve on the sensitivity of the initial detectors by about a factor of 10. The quantum nature of light will limit the sensitivity of these Advanced LIGO interferometers at most frequencies; new approaches to reducing the quantum noise will be needed to improve the sensitivity further. This quantum noise originates from the vacuum fluctuations that enter the unused port of the interferometer and interfere with the laser light. Vacuum fluctuations have the minimum noise allowed by Heisenberg's uncertainty principle, [Delta]X1 [Delta]X2 >/=1, where the two quadratures X1 and X2 are non-commuting observables responsible for the two forms of quantum noise, shot noise and radiation pressure noise. By replacing the vacuum fluctuations entering the interferometer with squeezed states, which have lower noise in one quadrature than the vacuum state, we have reduced the shot noise of a LIGO interferometer. The sensitivity to gravitational waves measured during this experiment represents the best sensitivity achieved to date at frequencies above 200 Hz, and possibly the first time that squeezing has been measured in an interferometer at frequencies below 700 Hz. The possibility that injection of squeezed states could introduce environmental noise couplings that would degrade the crucial but fragile low frequency sensitivity of a LIGO interferometer has been a major concern in planning to implement squeezing as part of baseline interferometer operations. These results demonstrate that squeezing is compatible with the low frequency sensitivity of a full scale gravitational wave interferometer. We also investigated the limits to the level of squeezing observed, including optical losses and fluctuations of the squeezing angle. The lessons learned should allow for responsible planning to implement squeezing in Advanced LIGO, either as an alternative to high power operation or an early upgrade to improve the sensitivity. This thesis is available at DSpace@MIT and has LIGO document number P1300006. by Sheila E Dwyer. Ph.D. 2013-07-09T19:30:26Z 2013-07-09T19:30:26Z 2013 2013 Thesis http://hdl.handle.net/1721.1/79427 850467045 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 223 p. application/pdf Massachusetts Institute of Technology |
| spellingShingle | Physics. Dwyer, Sheila E. (Sheila Elizabeth) Quantum noise reduction using squeezed states in LIGO |
| title | Quantum noise reduction using squeezed states in LIGO |
| title_full | Quantum noise reduction using squeezed states in LIGO |
| title_fullStr | Quantum noise reduction using squeezed states in LIGO |
| title_full_unstemmed | Quantum noise reduction using squeezed states in LIGO |
| title_short | Quantum noise reduction using squeezed states in LIGO |
| title_sort | quantum noise reduction using squeezed states in ligo |
| topic | Physics. |
| url | http://hdl.handle.net/1721.1/79427 |
| work_keys_str_mv | AT dwyersheilaesheilaelizabeth quantumnoisereductionusingsqueezedstatesinligo AT dwyersheilaesheilaelizabeth sensitivityimprovementofaligogravitationalwaynedetectorthroughsqueezedstateinjection |