Mechanical and optical thermal noises play an important role in many precise optomechanical experiments, in which positions of test bodies are monitored by laser beams. Much of the initial experimental and theoretical research in this area was driven by the physics of gravitational-wave interferometers, where thermal fluctuations are expected to be the dominant source of noise in the frequency band between about 10 and 100 Hz. Recently, it has become clear that controlling thermal noise will be key in several other fields, notably in designing laser cavities with higher frequency stability, in reaching the quantum limit in macroscopic opto-mechanical experiments, and in cavity QED experiments. In this chapter we review the statistical-mechanics formalism which is used to theoretically calculate mechanical and optical thermal noise. For completeness, we also add a discussion of another important limitation in mechanical measurements, the so-called Standard Quantum Limit.
|Title of host publication||Optical Coatings and Thermal Noise in Precision Measurement|
|Editors||Gregory Harry, Timothy P Bodiya, Riccardo DeSalvo|
|Place of Publication||New York NY USA|
|Publisher||Cambridge University Press|
|Number of pages||5|
|Publication status||Published - 1 Jan 2012|