The following article is a written version of the Richtmyer award lecture given to the annual meeting of the American Association of Physics Teachers in January 1996. I discuss the basic idea of Bose–Einstein condensation in a gas and how it has been produced and examined. To cool the atoms to the point of condensation we use laser cooling and trapping, followed by magnetic trapping and evaporative cooling. These techniques are explained, along with the signatures of Bose–Einstein condensation that we observe. I also discuss how very similar laser cooling and trapping techniques have been incorporated into undergraduate laboratory experiments.
The following article is a written version of the Richtmyer award lecture given to the annual meeting of the American Association of Physics Teachers in January 1996. I discuss the basic idea of Bose–Einstein condensation in a gas and how it has been produced and examined. To cool the atoms to the point of condensation we use laser cooling and trapping, followed by magnetic trapping and evaporative cooling. These techniques are explained, along with the signatures of Bose–Einstein condensation that we observe. I also discuss how very similar laser cooling and trapping techniques have been incorporated into undergraduate laboratory experiments.
Bose–Einstein condensation in a gas has now been achieved. Atoms are cooled to the point of condensation using laser cooling and trapping, followed by magnetic trapping and evaporative cooling. These techniques are explained, as well as the techniques by which we observe the cold atom samples. Three different signatures of Bose–Einstein condensation are described. A number of properties of the condensate, including collective excitations, distortions of the wave function by interactions, and the fraction of atoms in the condensate versus temperature, have also been measured.
Since an atomic Bose-Einstein condensate, predicted by Einstein in 1925, was first produced in the laboratory in 1995, the study of ultracold Bose and Fermi gases has become one of the most active areas in contemporary physics. This book explains phenomena in ultracold gases from basic principles, without assuming a detailed knowledge of atomic, condensed matter, and nuclear physics. This new edition has been revised and updated, and includes new chapters on optical lattices, low dimensions, and strongly-interacting Fermi systems. This book provides a unified introduction to the physics of ultracold atomic Bose and Fermi gases for advanced undergraduate and graduate students, as well as experimentalists and theorists. Chapters cover the statistical physics of trapped gases, atomic properties, cooling and trapping atoms, interatomic interactions, structure of trapped condensates, collective modes, rotating condensates, superfluidity, interference phenomena, and trapped Fermi gases. Problems are included at the end of each chapter.
Since an atomic Bose-Einstein condensate, predicted by Einstein in 1925, was first produced in the laboratory in 1995, the study of ultracold Bose and Fermi gases has become one of the most active areas in contemporary physics. This book explains phenomena in ultracold gases from basic principles, without assuming a detailed knowledge of atomic, condensed matter, and nuclear physics. This new edition has been revised and updated, and includes new chapters on optical lattices, low dimensions, and strongly-interacting Fermi systems. This book provides a unified introduction to the physics of ultracold atomic Bose and Fermi gases for advanced undergraduate and graduate students, as well as experimentalists and theorists. Chapters cover the statistical physics of trapped gases, atomic properties, cooling and trapping atoms, interatomic interactions, structure of trapped condensates, collective modes, rotating condensates, superfluidity, interference phenomena, and trapped Fermi gases. Problems are included at the end of each chapter.
Bose-Einstein condensates of dilute gases offer a rich field to study fundamental quantum-mechanical processes, manipulation of the speed at which light propogates, observation of atomic pair-formation and superfluidity, or even simulating white dwarf stars. Still more radical applications are on the horizon. However, their initial creation was a masterpiece of experimental physics. After an initial process of laser cooling (which itself won its developers the 1997 Nobel Prize), atoms in a magnetic-optical trap must be safely transferred into a purely magnetic trap, where the condensation process begins at 170 nK and 20 nK a pure condensate of 2000 atoms could be created. More astonishingly, Wieman and Cornell showed these low temperatures could be achieved in "bench scale" equipment rather than the massive pieces normally demanded by cryoscience. For their 1995 discovery of this new state of matter, they were awarded the 2001 Nobel Prize in Physics.
The recent developments in the study of Bose-Einstein condensation of neutral atoms are described. These studies aim to observe this phenomenon in a Bose gas where the quantum statistics of the particles, rather than the interactions between them, dominate the transition. The latest techniques use a combination of laser and evaporative cooling to get to the very low temperatures, in the nanokelvin regime, that are required to see condensation. In recent experiments at the Joint Institute for Laboratory Astrophysics of the University Colorado and the National Institute of Standards and Technology, Bose-condensed assemblies of rubidium atoms have been produced and their properties investigated. The relationship of this work to other phenomena in condensed matter and quantum field theory is discussed.