Atomic beams

Atomic beams

Unidirectional streams of neutral atoms passing through a vacuum. These atoms are virtually free from the influence of neighboring atoms but may be subjected to electric and magnetic fields so that their properties may be studied. The technique of atomic beams is identical to that of molecular beams. For historical reasons the latter term is most generally used to describe the method as applied to either atoms or molecules.

The method of atomic beams yields extremely accurate spectroscopic data about the energy levels of atoms, and hence detailed information about the interaction of electrons in the atom with each other and with the atomic nucleus, as well as information about the interaction of all components of the atom with external fields. See Molecular beams

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.
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A beam of atoms emerges from the oven at a temperature near 100 [degrees]C and travels through a spatially varying magnetic field, where the beam is split into two atomic beams with different magnetic states that follow different trajectories.
Cesium atoms are also relatively heavy and thus move at a relatively slow speed of about 130 m/s at room temperature in an atomic beam. This allows cesium atoms to be observed for a longer period than hydrogen atoms, for example, which travel much faster, about 1600 m/s, at room temperature.
Ramsey's new method interrogated the atoms with two short microwave pulses, separated by some distance in an atomic beam. Applying the oscillating field in two steps accomplished the goal of narrowing the resonance width.
A Historical Review of U.S. Contributions to the Atomic Redefinition of the SI Second in 1967
Grisham is a world leader in the development of high-power atomic beams based on the production of the unusual negatively charged hydrogen ion.
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They also suggest ways of constructing such gates out of quantum dots, atomic beams, or trapped ions interacting with laser beams.
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Drullinger, Velocity distributions of atomic beams by gated optical pumping, in Proc.
Because of the velocity spread in the atomic beam, this separation is not perfect, so some atoms in other [m.sub.F] states are mixed in with the ground-state atoms that go through the cav ity.
Briefly, it has a Ramsey cavity 1.55 m long and an atomic beam diameter of 3 mm.
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Metcalf predicts this method wil not only improve the quality of experiments involving atomic beams, atomic fountains (SN: 8/19/89, p.117) and laser colling (SN: 8/12/89, p.103) but also will help make possible the development of extremely precise atomic clocks and atomic gyroscopes.
Laser spotlight pinpoints atoms in motion
While other research teams work with fast-moving atomic beams, Chu slowly pumps laser-cooled atoms through his interferometer with an "atomic fountain" (SN:8/19/89, p.117).
In one such device, a calcium atomic beam is divided into four wave paths by two laser beams perpendicular to the atoms.
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This should yield an effect about 1,000 times larger, but experimentalists have not yet devised a way to produce atomic beams with the right characteristics for such an experiment.
Quantum interference: neutrons feel the effect of an electric field that apparently exerts no force

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