Results 161 to 170 of about 84,599 (217)
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Decoherence from spontaneous emission
Physical Review A, 1995Starting from a generalization of the Weisskopf-Wigner model for the case of a two-level atom with a largely spread center-of-mass wave function, we show that spatial correlations are destroyed to some extent by a spontaneously emitted photon. We derive a particularly simple form of the corresponding decoherence function and determine the dependence of
, Steuernagel, , Paul
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Physical Review A, 1970
Coherent spontaneous emission from a system of $N$ two-level atoms interacting with a quantized radiation field is treated for the case in which Dicke's "cooperation number" $r$ is macroscopically large. It is shown how to modify the quasiclassical approach to this problem to incorporate quantum effects that are lost in the self-consistent-field ...
Rodolfo Bonifacio, Giuliano Preparata
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Coherent spontaneous emission from a system of $N$ two-level atoms interacting with a quantized radiation field is treated for the case in which Dicke's "cooperation number" $r$ is macroscopically large. It is shown how to modify the quasiclassical approach to this problem to incorporate quantum effects that are lost in the self-consistent-field ...
Rodolfo Bonifacio, Giuliano Preparata
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American Journal of Physics, 1984
This paper is a discussion of that perennial question, ‘‘Why does an excited atom radiate?’’ A satisfactory physical picture emerges when proper account is taken of the interplay between radiation reaction and the (quantum-mechanical) zero-point fluctuations of the radiation field.
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This paper is a discussion of that perennial question, ‘‘Why does an excited atom radiate?’’ A satisfactory physical picture emerges when proper account is taken of the interplay between radiation reaction and the (quantum-mechanical) zero-point fluctuations of the radiation field.
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IEEE Journal of Quantum Electronics, 1988
The problem of the spontaneous emission from a single excited two-level atom in the presence of N unexcited similar atoms is discussed. A formalism is presented for evaluation of the time-development operator (and thus the density matrix) which has certain desirable features for time-dependent problems in the area, e.g. of atom-field interactions, when
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The problem of the spontaneous emission from a single excited two-level atom in the presence of N unexcited similar atoms is discussed. A formalism is presented for evaluation of the time-development operator (and thus the density matrix) which has certain desirable features for time-dependent problems in the area, e.g. of atom-field interactions, when
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Relativistic theory of spontaneous emission
Physical Review A, 1988We derive a formula for the relativistic decay rates in atoms in a formulation of quantum electrodynamics based upon the electron's self-energy. Relativistic Coulomb wave functions are used, the full spin calculation is carried out, and the dipole approximation is not employed.
, Barut, , Salamin
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Spontaneous otoacoustic emissions in schoolchildren
International Journal of Pediatric Otorhinolaryngology, 2016Spontaneous otoacoustic emissions (SOAEs) are one of the least studied types of otoacoustic emissions (OAEs). The purpose of this study was twofold: first, to determine the prevalence of SOAEs in schoolchildren, and second to test whether there was dependence between the presence or absence of SOAEs in a subject and the corresponding level of their ...
W. Wiktor Jedrzejczak +3 more
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Inhibited Spontaneous Emission
Physical Review Letters, 1981The radiative properties of an atom in a cavity differ fundamentally from the atom's radiative properties in free space. Spontaneous emission is inhibited if the cavity has characteristic dimensions which are small compared to the radiation wavelength, and enhanced if the cavity is resonant.
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Controlling spontaneous emission with metamaterials
Optics Letters, 2010We have observed, in metamaterial with hyperbolic dispersion (an array of silver nanowires in alumina membrane), a sixfold reduction of the emission lifetime of dye deposited onto the metamaterial's surface. This serves as evidence of an anomalously high density of photonic states in hyperbolic metamaterials, demonstrates the feasibility of an earlier ...
M A, Noginov +9 more
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Observation of inhibited spontaneous emission
Physical Review Letters, 1985The radiative decay of the cyclotron motion of a single electron is significantly inhibited when the electron is located within microwave cavity (formed by the electrodes of a Penning trap) rather than in free space. This is the first observation of such inhibited spontaneous emission and the first use of a promising new system for radiative physics ...
, Gabrielse, , Dehmelt
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Spontaneous emission of Alfvénic fluctuations
Plasma Physics and Controlled Fusion, 2017Low-frequency fluctuations are pervasively observed in the solar wind. The present paper theoretically calculates the steady state spectra of low-frequency electromagnetic (EM) fluctuations of the Alfvenic type for thermal equilibrium plasma. The analysis is based upon a recently formulated theory of spontaneously emitted EM fluctuations in magnetized ...
Yoon, P. H. +4 more
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