Author: Alexander J. Dunning
Publisher: Springer
Published: 2015-08-18
Total Pages: 170
ISBN-13: 3319217380
DOWNLOAD EBOOK →This work unites the concepts of laser cooling and matter-wave interferometry to develop an interferometric laser cooling technique in an experimental system of cold rubidium atoms. Serving as an introduction to graduate level coherent optical atomic manipulation, the thesis describes the theory of stimulated Raman transitions and atom interferometry, along with the experimental methods for preparing and manipulating cold atoms, before building on these foundations to explore tailored optical pulse sequences and novel atomic cooling techniques. Interferometric cooling, originally proposed by Weitz and Hänsch in 2000, is based upon the coherent broadband laser pulses of Ramsey interferometry and in principle allows laser cooling of atomic and molecular species outside the scope of traditional Doppler laser cooling. On the path toward cooling, composite pulses – quantum error correction methods, developed by chemists to mitigate the effects of in homogeneities in NMR spectroscopy – are investigated with a view to improving the performance of atom interferometers.
Author: Paul R. Berman
Publisher: Academic Press
Published: 1997-01-08
Total Pages: 497
ISBN-13: 008052768X
DOWNLOAD EBOOK →The field of atom interferometry has expanded rapidly in recent years, and todays research laboratories are using atom interferometers both as inertial sensors and for precision measurements. Many researchers also use atom interferometry as a means of researching fundamental questions in quantum mechanics. Atom Interferometry contains contributions from theoretical and experimental physicists at the forefront of this rapidly developing field. Editor Paul R. Berman includes an excellent balance of background material and recent experimental results,providing a general overview of atom interferometry and demonstrating the promise that it holds for the future. Includes contributions from many of the research groups that have pioneered this emerging field Discusses and demonstrates new aspects of the wave nature of atoms Explains the many important applications of atom interferometry, from a measurement of the gravitational constant to atom lithography Examines applications of atom interferometry to fundamentally important quantum mechanics problems
Author: Kathy Levin
Publisher: Elsevier
Published: 2012-11-15
Total Pages: 225
ISBN-13: 0444538623
DOWNLOAD EBOOK →The rapidly developing topic of ultracold atoms has many actual and potential applications for condensed-matter science, and the contributions to this book emphasize these connections. Ultracold Bose and Fermi quantum gases are introduced at a level appropriate for first-year graduate students and non-specialists such as more mature general physicists. The reader will find answers to questions like: how are experiments conducted and how are the results interpreted? What are the advantages and limitations of ultracold atoms in studying many-body physics? How do experiments on ultracold atoms facilitate novel scientific opportunities relevant to the condensed-matted community? This volume seeks to be comprehensible rather than comprehensive; it aims at the level of a colloquium, accessible to outside readers, containing only minimal equations and limited references. In large part, it relies on many beautiful experiments from the past fifteen years and their very fruitful interplay with basic theoretical ideas. In this particular context, phenomena most relevant to condensed-matter science have been emphasized. Introduces ultracold Bose and Fermi quantum gases at a level appropriate for non-specialists Discusses landmark experiments and their fruitful interplay with basic theoretical ideas Comprehensible rather than comprehensive, containing only minimal equations
Author: Kayleigh Cassella
Publisher:
Published: 2018
Total Pages: 193
ISBN-13:
DOWNLOAD EBOOK →Ushered forth by advances in time and frequency metrology, atom interferometry remains an indispensable measurement tool in atomic physics due to its precision and versatility. A sequence of four $\pi/2$ beam splitter pulses can create either an interferometer sensitive to the atom's recoil frequency when the momentum imparted by the light reverses direction between pulse pairs or, when constructed from pulses without such reversal, sensitive to the perturbing potential from an external optical field. Here, we demonstrate the first atom interferometer with laser-cooled lithium, advantageous for its low mass and simple atomic structure. We study both a recoil-sensitive Ramsey-Bord\'e interferometer and interferometry sensitive to the dynamic polarizability of the ground state of lithium. Recoil-sensitive Ramsey-Bord\'e interferometry benefits from lithium's high recoil frequency, a consequence of its low mass. At an interrogation time of 10 ms, a Ramsey-Bord\'e lithium interferometer could achieve sensitivities comparable to those realized at much longer times with heavier alkali atoms. However, in contrast with other atoms that are used for atom interferometry, lithium's unresolved excited-state hyperfine structure precludes the the cycling transition necessary for efficient cooling. Without sub-Doppler cooling techniques. As as result, a lithium atomic gas is typically laser cooled to temperatures around 300 $\mu$K, above the Doppler limit, and well above the recoil temperature of 6 $\mu$K. This higher temperature gas expands rapidly during the operation of an atom interferometer, limiting the experimental interrogation time and preventing spatially resolved detection. In this work, a light-pulse lithium matter-wave interferometer is demonstrated in spite of these limitation. Two-photon Raman interferometer pulses coherently couple the atom's spin and momentum and are thus able to spectrally resolve the outputs. These fast pulses drive conjugate interferometers simultaneously which beat with a fast frequency component proportional to the atomic recoil frequency and an envelope modulated by the two-photon detuning of the Raman transition. We detect the summed signal at short experimental times, preventing perturbation of the signal from vibration noise. This demonstration of a sub-recoil measurement with a super-recoil sample opens the door to similar scheme with other particles that are difficult to trap and cool well, like electrons. An interferometer instead composed of $\pi/2$-pulses with a single direction of momentum transfer, can be sensitive to the dynamic polarizability of the atomic ground state. By scanning the frequency of an external driving field, such a measurement can be used to determine the atom's tune-out wavelength. This is the wavelength at which the frequency-dependent polarizability vanishes due to compensating ac-Stark shifts from other atomic states. Lithium's simple atomic structure allows for a precise computation of properties with only {\em ab initio} wave functions and spectroscopic data. A direct interferometric measurement of lithium's red tune-out wavelength at 670.971626(1) nm, is a precise comparison to existing `all-order' atomic theory computations. It also provides another way to experimentally determine the $S-$ to $P-$ transitions matrix elements, for which large correlations and small values complicate computations. Finally, a future measurement of lithium's ultraviolet tune-out wavelength of at 324.192(2) nm would be sensitive to relativistic approximations in the atomic structure description. Atom interferometry simultaneously verifies existing atomic theory with measurements of atomic properties and searches for exotic physics lurking in plain sight. The techniques developed here broaden the applicability of interferometry and increase measurement sensitivity by simplifying cooling, increasing atom number and reducing the cycle time. Overcoming the current experimental limitations on interrogation time would allow for ultra-precise measurements of both the tune-out wavelength and the fine structure constant.
Author: Harold J. Metcalf
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 329
ISBN-13: 146121470X
DOWNLOAD EBOOK →Intended for advanced undergraduates and beginning graduates with some basic knowledge of optics and quantum mechanics, this text begins with a review of the relevant results of quantum mechanics, before turning to the electromagnetic interactions involved in slowing and trapping atoms and ions, in both magnetic and optical traps. The concluding chapters discuss a broad range of applications, from atomic clocks and studies of collision processes, to diffraction and interference of atomic beams at optical lattices and Bose-Einstein condensation.
Author:
Publisher:
Published: 1997
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOK →We have developed a cold atomic beam source to be used as the input beam for a three-grating atom interferometer. Using laser cooling and trapping techniques, we have slowed and cooled a thermal atomic beam, trapped the slow atoms, and redirected them into a cold beam with an adjustable velocity. The cold atomic beam has a temperature of approximately 500 muK and has a controllable velocity from 2-20 in/s. The gratings for the interferometer have been microfabricated in silicon nitride and have a grating spacing of 250 nm.
Author: Galina Nemova
Publisher: CRC Press
Published: 2016-10-26
Total Pages: 478
ISBN-13: 9814745057
DOWNLOAD EBOOK →In the recent decades, laser cooling or optical refrigeration—a physical process by which a system loses its thermal energy as a result of interaction with laser light—has garnered a great deal of scientific interest due to the importance of its applications. Optical solid-state coolers are one such application. They are free from liquids as well as moving parts that generate vibrations and introduce noise to sensors and other devices. They are based on reliable laser diode pump systems. Laser cooling can also be used to mitigate heat generation in high-power lasers. This book compiles and details cutting-edge research in laser cooling done by various scientific teams all over the world that are currently revolutionizing optical refrigerating technology. It includes recent results on laser cooling by redistribution of radiation in dense gas mixtures, three conceptually different approaches to laser cooling of solids such as cooling with anti-Stokes fluorescence, Brillouin cooling, and Raman cooling. It also discusses crystal growth and glass production for laser cooling applications. This book will appeal to anyone involved in laser physics, solid-state physics, low-temperature physics or cryogenics, materials research, development of temperature sensors, or infrared detectors.
Author: David Marvin Slaughter Johnson
Publisher: Stanford University
Published: 2011
Total Pages: 152
ISBN-13:
DOWNLOAD EBOOK →Due to its impressive sensitivity, long baseline atom interferometry is an exciting tool for tests of fundamental physics. We are currently constructing a 10-meter scale apparatus to test the Weak Equivalence Principle (WEP) using co-located Rb85 and Rb87 atom interferometers. This apparatus aims to improve the current limit on WEP violation 100-fold, which illustrates the power of this technique. This scientific goal sets stringent requirements on the kinematic preparation of the atomic test masses, the interferometer laser wavefront and stability, as well as the electromagnetic and gravitational field homogeneity of the interferometer region. The efforts to control these sources of systematic error are discussed. Additionally, applications of long baseline atom interferometry to space-based sensors for geodesy and gravitational wave detection are presented.
Author: E. Arimondo
Publisher: North Holland
Published: 1992
Total Pages: 820
ISBN-13:
DOWNLOAD EBOOK →The recent fascinating progress on laser cooling is the result of the close connection between theoretical work and the rapid technological advances in laser sources, particularly in the field of powerful semiconductor and solid-state lasers operating over a wide range of optical and near-infrared frequencies. The very close international and personal collaboration amongst the researchers resulting in a direct link between experimental data and theoretical calculations which characterize work in this field, have been important factors in the rapid comprehension of the subtle and beautiful phenomena involved in laser manipulation. This Enrico Fermi school is the first formal school fully devoted to this topic. The theoretical part of the book includes contributions on the framework for the study of the photon momentum exchanges in the absence of relaxation, recent mechanisms of laser cooling, an analysis of the cooling forces, analysis of atomic and molecular beams, cooling through coherent population trapping and the relation between laser cooling and quantum nondemolition measurements. The experimental section deals with topics such as, an analysis of atomic and molecular beams, methods and applications of laser cooling, advances in laser cooling and the new exciting field of atomic interferometry. All students and researchers working in this field will welcome this excellent review of research and progress in laser cooling, so strongly linked to the fundamental understanding of physics.