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Spontaneous Emission Revisited
Physica Status Solidi (a), 1980The cause of spontaneous emission is frequently assigned to the presence of zero-point energy in the radiation field. As such it would have no classical equivalent since zero-point energy does not exist classically. It is argued that spontaneous emission is not caused by zero-point energy but rather by an essentially classical interaction between the ...
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Spontaneous otoacoustic emissions in a dog
Hearing Research, 1984Intense (up to 59 dB SPL) spontaneous otoacoustic emissions are produced by both ears of a young dog. The right ear produces a single, very narrow-band (less than 4 Hz) emission at about 9100 Hz. Brainstem evoked-response audiometry suggests that this emission is generated near the transition between normal and abnormal regions of the cochlea.
M A, Ruggero, B, Kramek, N C, Rich
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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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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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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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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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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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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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A Case of 'Spontaneous Otoacoustic Emission'
Archives of Otolaryngology - Head and Neck Surgery, 1987A 25-year-old man produced a continuous high-pitched pure tone (6.1 kHz, 37.2-dB sound pressure level) in his right ear. The tone was not audible to the patient. He had sensorineural deafness over 1 kHz with a dip of 45 dB at 6 kHz. The tone was considered to be emitted through the eardrum from the inner ear, ie, a "spontaneous otoacoustic emission".
E, Yamamoto +3 more
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