Effect of quantum fluctuations on soliton regimes in microlasers

Abstract We present a theoretical investigation of effect of quantum fluctuations on laser solitons. Derivation of the stochastic equation, linearized with respect to quantum perturbations is carried out and the solutions are found. Explicit expressions are obtained for the time dependence of the soliton coordinates and momentum dispersion (variance) for perturbations averaged over the reservoir. It is shown that the dispersion of the soliton momentum becomes constant. It is shown that the dispersion of quantum perturbations tends to infinity near the Andronov-Hopf bifurcation threshold. The magnitude of quantum perturbations near the threshold of the appearance of hysteresis is estimated. It is shown that quantum perturbations do not significantly noise the soliton profile even with a very low intensity tending to zero. The number of photons in such solitons without supporting radiation, can reach unity.

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Effects of plastic anisotropy on localization in orthotropic materials: new explicit expressions for the orientation of localization bands in flat specimens subjected to uniaxial tension

10.31224/osf.io/45wcs ◽

2020 ◽

Author(s):

Jose Rodriguez-Martinez ◽

Oana Cazacu

Keyword(s):

Uniaxial Tension ◽

Theoretical Investigation ◽

Plastic Anisotropy ◽

Orthotropic Materials ◽

Uniaxial Tensile ◽

Experimental Measurements ◽

Plastic Localization ◽

Metallic Sheet ◽

First Time ◽

Explicit Expressions

This paper presents a theoretical investigation on the inception of plastic localization bands in specimens taken from orthotropic metallic sheets, and subjected to uniaxial tension. For the first time, it is shown that the orientations of the localization bands can be obtained directly from experimental measurements of the uniaxial tensile flow stresses and Lankford coefficients (r-values) of the metallic sheet.

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Equatorial auroral records reveal dynamics of the paleo-West Pacific geomagnetic anomaly

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2026080118 ◽

2021 ◽

Vol 118 (20) ◽

pp. e2026080118

Author(s):

Fei He ◽

Yong Wei ◽

Stefano Maffei ◽

Philip W. Livermore ◽

Christopher J. Davies ◽

...

Keyword(s):

Time Dependence ◽

Radiation Belt ◽

Flow Model ◽

Core Flow ◽

West Pacific ◽

Naked Eye ◽

Low Intensity ◽

Geomagnetic Anomaly ◽

Geomagnetic Models ◽

Geomagnetic Intensity

Localized regions of low geomagnetic intensity such as the South Atlantic Anomaly allow energetic particles from the Van Allen radiation belt to precipitate into the atmosphere and have been linked to a signature in the form of red aurora–like airglow visible to the naked eye. Smoothed global geomagnetic models predict a low-intensity West Pacific Anomaly (WPA) during the sixteenth to nineteenth centuries characterized by a simple time dependence. Here, we link the WPA to an independent database of equatorial aurorae recorded in Seoul, South Korea. These records show a complex fluctuating behavior in auroral frequency, whose overall trend from 1500 to 1800 AD is consistent with the locally weak geomagnetic field of the WPA, with a minimum at 1650 AD. We propose that the fluctuations in auroral frequency are caused by corresponding and hitherto unknown fluctuations in the regional magnetic intensity with peaks at 1590 and 1720 AD, a time dependence that has been masked by the smoothing inherent in regularized global geomagnetic models. A physical core flow model demonstrates that such behavior requires localized time-dependent upwelling flows in the Earth’s core, possibly driven by regional lower-mantle anomalies.

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ABOUT QUANTUM FLUCTUATIONS AND HOLOGRAPHIC PRINCIPLE IN (4+n)-DIMENSIONAL SPACETIME

Modern Physics Letters A ◽

10.1142/s0217732306020469 ◽

2006 ◽

Vol 21 (13) ◽

pp. 1041-1047 ◽

Cited By ~ 1

Author(s):

P. MIDODASHVILI

Keyword(s):

Black Holes ◽

Quantum Fluctuations ◽

Holographic Principle ◽

Typical Size ◽

Dimensional Spacetime ◽

Galactic Sources ◽

Spacetime Fluctuations ◽

Numerical Estimations ◽

Explicit Expressions

Here we present explicit expressions for quantum fluctuations of spacetime in the case of (4+n)-dimensional spacetimes, and consider their holographic properties and some implications for clocks, black holes and computation. We also consider quantum fluctuations and their holographic properties in ADD model and estimate the typical size and mass of the clock to be used in precise measurements of spacetime fluctuations. Numerical estimations of phase incoherence of light from extra-galactic sources in ADD model are also presented.

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Improvement of the Stability of X-Ray Emission by Thermal Excitation of a Pyroelectric Single Crystal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.582.174 ◽

2013 ◽

Vol 582 ◽

pp. 174-177 ◽

Cited By ~ 1

Author(s):

Fumihiko Naruse ◽

Hiroyuki Honda ◽

Yoshikazu Nakanishi ◽

Shinji Fukao ◽

Yuuki Sato ◽

...

Keyword(s):

Time Dependence ◽

Temperature Cycle ◽

Cycle Period ◽

Thermal Excitation ◽

Crystal Temperature ◽

X Ray ◽

Low Intensity ◽

Creeping Discharge ◽

The Stability ◽

Pyroelectric Crystals

X-ray emission using pyroelectric crystals is intermittent, and has low intensity and stability. One of the factors for low stability is related to creeping discharge, due to the accumulation of surface electric charges that change in response to the temperature. The time dependence of the net amount of electric charge was investigated by changing the cycle period of the crystal temperature. The stability of the X-ray emission is demonstrated to be strongly dependent on the temperature cycle period.

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Time dependence of quantum fluctuations in solitons

Optics Letters ◽

10.1364/ol.14.000373 ◽

1989 ◽

Vol 14 (7) ◽

pp. 373 ◽

Cited By ~ 41

Author(s):

P. D. Drummond ◽

S. J. Carter ◽

R. M. Shelby

Keyword(s):

Time Dependence ◽

Quantum Fluctuations

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The O–C diagrams of minor planets − a new approach to modelling the rotation

International Astronomical Union Colloquium ◽

10.1017/s0252921100031407 ◽

1999 ◽

Vol 173 ◽

pp. 185-188

Author(s):

Gy. Szabó ◽

K. Sárneczky ◽

L.L. Kiss

Keyword(s):

Error Analysis ◽

Time Dependence ◽

Theoretical Work ◽

Minor Planet ◽

Minor Planets ◽

New Approach ◽

Preliminary Results ◽

Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

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