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Two-Level Approximation in Atomic Systems
American Journal of Physics, 1974In analyzing atomic systems undergoing interactions with external fields that are nearly resonant with two, and only two of the atom's energy levels, one commonly employs a two-level or resonance approximation in which all states of the atom are neglected except for the two in resonance with the field.
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Two-Level Atom in a Standing, Electromagnetic Wave
International Journal of Theoretical Physics, 2003zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Su, Kalin +3 more
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The damped driven two-level atom
Annals of Physics, 1969Abstract Equations are derived for the time evolution of the reduced density operator for a driven two-level atom which is damped by its coupling to a (zero-temperature) bath. Explicit solutions are obtained for the case in which the driving field oscillates harmonically. The effect of field statistics is discussed.
B.R Mollow, M.M Miller
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Self-field quantum electrodynamics: The two-level atom
Physical Review A, 1990We use a self-field approach to quantum electrodynamics (QED) to show how one may obtain spontaneous emission and the Lamb shift in a two-level atom without second quantization of the radiation field. In addition, we compare the self-field formalism to that of the neoclassical theory of electrodynamics advanced by Crisp and Jaynes [Phys. Rev. 179, 1253
, Barut, , Dowling
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Cone emission from laser-pumped two-level atoms
Physical Review A, 1991In spite of the fact that cone emission was first observed over a decade ago, there is still no generally accepted theory of the effect. Here we give an outline of a unified approach and point out a mechanism that supports Cherenkov-type radiation due to vacuum fluctuations as a possible source of cone emission.
, You, , Mostowski, , Cooper, , Shuker
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Optical bistability with two-level atoms
2008Since the first observation of optical bistability in 1976 (1), a large number of investigations of this phenomenon have appeared in the literature (2). Of particular theoretical interest has been the bistable system composed of “two-level” atoms within an optical resonator.
Kimble, H. J. +3 more
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Two-level atom shows photon antibunching
Physics Today, 1978What happens to a two-level atom in an intense laser field? The system resembles the hydrogen atom in its relative simplicity, but only in the last couple of years have experiments shed much light on its behavior. Intensity-dependent resonant light scattering has been studied in two-level atoms by looking at the spectrum and more recently, by observing
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Probe Spectroscopy of Two-Level Atoms
Physica Scripta, 1982The effects of a strong standing wave field on the absorption behaviour of a weak probe field are studied. An absorptive medium is assumed to consist of stationary two-level atoms with arbitrary decay and pumping scheme. The spectrum with a resonant saturator does not exhibit emissive behaviour as in the travelling wave cases.
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Two-Level Atoms and Spontaneous Emission
1999The damped harmonic oscillator provides our elementary description for the electromagnetic field in a lossy cavity. The damped two-level atom will provide our elementary description for the matter with which this field interacts. In an atomic vapor, loss of energy from an excited atom may take place via spontaneous emission or inelastic collisions ...
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Preparation of atomic sodium as a two-level atom
Optics Communications, 1974Abstract A method of preparing atomic sodium so that it behaves, to a first approximation, as a simple two-level atom is presented. The procedure consists of a succession of optical pumpings by a c.w. dye laser of a thermal atomic beam of sodium.
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