Mow-Lowry, CSheard, BGray, Malcolm BMcClelland, DavidWhitcomb, Stanley Ernest2009-09-102010-12-202009-09-102010-12-20Physical Review Letters 92.16 (2004): 161102/1-40031-90071079-7114http://hdl.handle.net/10440/825http://digitalcollections.anu.edu.au/handle/10440/825We present results that are a classical analog to quantum noise cancellation. It is possible to breach the standard quantum limit in an interferometer by the use of squeezing to correlate orthogonal quadratures of quantum noise, causing their effects on the resulting sensitivity to cancel. A laser beam incident on a Fabry-Perot cavity was imprinted with classical, correlated noise in the same quadratures that cause shot noise and radiation pressure noise. Couplings between these quadratures due to a movable mirror, sensitive to radiation pressure, cause the excess classical noise to cancel. This cancellation was shown to improve the signal to noise ratio of an injected signal by approximately a factor of 10.4 pageshttp://www.sherpa.ac.uk/romeo/index.php "Author can archive pre-print (ie pre-refereeing) … post-print (ie final draft post-refereeing) … [and] publisher's version/PDF. Link to publisher version … [and] Copyright notice required. Publisher's version/PDF can be used on … employers web site." - from SHERPA/RoMEO site (as at 25/02/10). ©2004 The American Physical SocietyKeywords: Amplitude modulation; Attenuation; Continuum mechanics; Fabry-Perot interferometers; Frequency modulation; Laser beams; Modulators; Noise abatement; Optical beam splitters; Oscillators (mechanical); Photodetectors; Quantum optics; Quantum theory; Shot noi2004-04-2310.1103/PhysRevLett.92.1611022015-12-11