Matter-wave interferometer

Inertial sensors are useful devices in both science and industry. Higher precision sensors could find practical scientific applications in the areas of general relativity (Chow et ah, 1985), geodesy and geology. Important applications of such devices occur also in the field of navigation, surveying and analysis of earth structures. Matter-wave interferometry has recently shown its potential to be an extremely sensitive probe for inertial forces (Clauser, 1988). First, neutron interferometers have been used to measure the Earth rotation (Colella et ah, 1975) and the acceleration due to gravity (Werner et ah, 1979) in the end of the seventies. In 1991, atom interference techniques have been used in... 

Principle of a light pulse matter-wave interferometer... 

C. Borde in Matter-wave interferometers a synthetic approach , in Atom Interferometry, edited by P. Berman (Academic Press, 1997), pp. 257-297... 

Formally, we describe the state of the particle during the propagation as a coherent superposition of states, in particular of position states, that are classically mutually exclusive. A classical object will either take one or the other path for sure. A quantum object cannot be said to do that since the intrinsic information content of the quantum system is insufficient to allow such a description [Brukner 2002], Matter wave interferometers prove this experimentally. The intriguing part is that a full interference visibility can only be obtained if we exclude all possibilities of detecting, even in principle, the... 

Fig. 9.70 Optical Ramsey scheme of an atomic beam passing through four traveling laser fields, interpreted as matter-wave interferometer. Solid lines represent the high-frequency recoil components, dotted lines the low-frequency components (only those traces leading to Ramsey resonances in the fourth zone are drawn) [1290]...

Matter-wave interferometry has found wide applications for testing basic laws of physics. One advantage of interferometry with massive particles, for instance, is the possibility of studying gravitational effects. Compared to the neutron interferometer, atomic interferometry can provide atomic fluxes that are many orders of magnitude higher than thermalized neutron fluxes from reactors. The sensitivity is therefore higher and the costs are much lower. 

A beam of slow atoms can be manipulated in many ways. This is performed within the field of atom optics [9.445-9.447]. An atomic beam can be bent or focused using laser fields. An atomic beam can also be reflected at an optical surface using the evanescent optical field from a laser beam reflected from the other side of the surface. The atom version of the Yoimg double-slit experiment has been performed, even with monochromatic thermal atoms, showing clearly the existence of matter waves [9.448]. Beam splitters for slow atomic beams can be optically achieved to build atomic interferometers based on de Broglie wave interference. The thermal de Broglie wavelength... 

F. Riehle, Th. Kisteers, A. White, J. Helmecke, Ch.J. Borde Optical Ramsey spectroscopy in a rotating frame Sagnac effect in a matter-wave interferometer. Phys. Rev. Lett. 67, 177 (1991)... 

Wise, J.L. and L.C. Chhabildas (1986), Laser Interferometer Measurements of Refractive Index in Shock-Compressed Materials, in Shock Waves in Condensed Matter (edited by Y.M. Gupta), Plenum, New York, pp. 441-454. 

No matter what modulation frequency is used for PA/FT-IR spectrometry, the bands from the upper layers of the sample always dominate the spectrum. In addition, the fact that the thermal wave decay length varies as when the spectra are measured with a rapid-scanning interferometer has always led to suboptimal results. The variation of L with wavenumber may be circumvented through the use of a phase-modulated step-scan interferometer, and most contemporary PA/FT-IR spectra are now measured with this type of instrument. 

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