共查询到20条相似文献,搜索用时 10 毫秒
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Theoretical analysis of measurement errors caused by the imperfection of the sensing optical loop in a glass block Faraday
effect current sensor has been presented. The experimental results with the fabricated sensor which was designed to achieve
a closed homogeneous and isotropic optical path show the importance of the perfectly isotropic and closed loop, in accordance
with the theoretical consideration. 相似文献
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4.
Dana S. Fields 《Foundations of Physics Letters》1999,12(1):67-79
A single classical isoergic particle was placed in a cube and allowed to propagate for 100 ns to 10 ms. The interaction of
the particle with the inner wall of the cube was modeled as a linear combination of specular and random reflection, the extent
of the combination being governed by a user-defined “roughness” parameter α. As a function of α, the particle’s relative pressure
and density spontaneously took on an inhomogenous distribution. 相似文献
5.
This paper shows that a substantial amount of dissipationless
spin-Hall current contribution may exist in the extrinsic spin-Hall
effect, which originates from the spin-orbit coupling induced by
the applied external electric field itself that drives the extrinsic
spin-Hall effect in a nonmagnetic semiconductor (or metal). By
assuming that the impurity density is in a moderate range such that
the total scattering potential due to all randomly distributed
impurities is a smooth function of the space coordinate, it is shown
that this dissipationless contribution shall be of the same orders
of magnitude as the usual extrinsic contribution from spin-orbit
dependent impurity scatterings (or may even be larger than the
latter one). The theoretical results obtained are in good agreement
with recent relevant experimental results. 相似文献
6.
潮汐对地球自转阻滞作用的估计 总被引:1,自引:0,他引:1
讨论了潮汐阻滞地球自转的机制,利用一个简化的模型计算了由潮汐引起的地球自转角加速度的数量级,得到了比较满意的结果,并讨论了几个简化假设的合理性,还利用该模型计算了当地球自转速度不再变化时的几个数据. 相似文献
7.
J. V. Michalowicz J. M. Nichols F. Bucholtz C. C. Olson 《Journal of statistical physics》2009,136(1):89-102
This work derives a version of Isserlis’ theorem for the specific case of four mixed-Gaussian random variables. The theorem
is then used to derive an expression for the auto-bispectral density for quadratically nonlinear systems driven with mixed-Gaussian
iid noise.
C.C. Olson is a NRC Postdoctoral Research Associate. 相似文献
8.
Christo I. Christov 《Foundations of Physics》2006,36(11):1701-1717
Maxwell accounted for the apparent elastic behavior of the electromagnetic field by augmenting Ampere’s law with the so-called displacement current, in much the same way that he treated the viscoelasticity of gases. Maxwell’s original constitutive relations for both electrodynamics and fluid dynamics were not material invariant. In the theory of viscoelastic fluids, the situation was later corrected by Oldroyd, who introduced the upper-convective derivative. Assuming that the electromagnetic field should follow the general requirements for a material field, we show that if the upper convected derivative is used in place of the partial time derivative in the displacement current term, Maxwell’s electrodynamics becomes material invariant. Note, that the material invariance of Faraday’s law is automatically established if the Lorentz force is admitted as an integral part of the model. The new formulation ensures that the equation for conservation of charge is also material invariant in vacuo. The viscoelastic medium whose apparent manifestation are the known phenomena of electrodynamics is called here the metacontinuum. 相似文献
9.
J. P. Wesley 《Foundations of Physics Letters》1994,7(1):95-104
Contrary to Northrup's claim, the pinch effect, predicted by either the Biot-Savart law or the original Ampere law, accounts for less than half the necessary force to drive Hering's pump. The longitudinal Ampere tension, which is not predicted by the Biot-Savart law, is sufficient to account for the remaining force necessary. 相似文献
10.
An intrinsic contribution to the spin Hall effect in two‐dimensional silicene is considered theoretically within the linear response theory and Green's function formalism. When an external voltage normal to the silicene plane is applied, the spin Hall conductivity is shown to reveal a transition from the spin Hall insulator phase at low bias to the conventional insulator phase at higher voltages. This transition resembles the recently reported phase transition in bilayer graphene. The spin–orbit interaction responsible for this transition in silicene is much stronger than in graphene, which should make the transition observable experimentally. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
11.
Friedhard Römer Bernd Witzigmann Oscar Chinellato Peter Arbenz 《Optical and Quantum Electronics》2007,39(4-6):341-352
Photonic crystal cavities facilitate novel applications demanding the efficient emission of incoherent light. This unique
property arises when combining a relatively high quality factor of the cavity modes with a tight spatial constriction of the
modes. While spontaneous emission is desired in these applications the stimulated emission must be kept low. A measure for
the spontaneous emission enhancement is the local density of optical states (LDOS). Due to the complicated three dimensional
geometry of photonic crystal cavities the LDOS quantity has to be computed numerically. In this work, we present the computation
of the LDOS by means of a 3D Finite Element (FE) Maxwell Solver. The solver applies a sophisticated symmetry handling to reduce
the problem size and provides perfectly matched layers to simulate open boundaries. Different photonic crystal cavity designs
have been investigated for their spontaneous emission enhancement by means of this FE solver. The simulation results have
been compared to photoluminescence characterizations of fabricated cavities. The excellent agreement of simulations and characterizations
results confirms the performance and the accuracy of the 3D FE Maxwell Solver. 相似文献
12.
K. A. Bronnikov S. A. Kononogov V. N. Melnikov 《General Relativity and Gravitation》2006,38(7):1215-1232
We discuss possible variations of the effective gravitational constant with length scale, predicted by most of alternative theories of gravity and unified models of physical interactions. After giving a brief general exposition, we review in more detail the predicted corrections to Newton’s law of gravity in diverse brane world models. We consider various configurations in 5 dimensions (flat, de Sitter and AdS branes in Einstein and Einstein–Gauss–Bonnet theories, with and without induced gravity and possible incomplete graviton localization), 5D multi-brane systems and some models in higher dimensions. A common feature of all models considered is the existence of corrections to Newton’s law at small radii comparable with the bulk characteristic length: at such radii, gravity on the brane becomes effectively multidimensional. Many models contain superlight perturbation modes, which modify gravity at large scale and may be important for astrophysics and cosmology. 相似文献
13.
This paper discusses studies of the migration over time of hypocenters from great depths to the Earth’s surface. The calculations are based on the notion that surface fracturing of the external lithosphere corresponds to brittle fracturing, while internal lithosphere fracturing, accompanied by a decrease of earthquake hypocenter depth, corresponds to ductile fracturing. A procedure for calculating periods of the rising of earthquake sources in an elastic-plastic environment is suggested. Finally, it was revealed that the rising of hypocenters to the surface takes approximately 8–10 years. 相似文献
14.
We calculate localization corrections to the anomalous Hall conductivity in the framework of side-jump and skew scattering mechanisms. In contrast to the ordinary Hall effect, there exists a nonvanishing localization correction to the anomalous Hall resistivity. The correction to the anomalous Hall conductivity vanishes in case of side-jump mechanism, but is nonzero for the skew scattering. 相似文献
15.
Minghao Ding Hong Li Yongjie Ding Hui Liu Daren Yu Xiaogang Wang 《Physics letters. A》2019,383(25):3108-3113
This paper experimentally evaluated the effect of the disruption of the symmetrical distribution of the propellant on the characteristics of the anode current. The change in the asymmetry degree of the propellant distribution is achieved by supplying gas with a dual-cavity gas distributor. The results show that as the asymmetry degree increases, the magnitude of the anode current changes monotonically from a slow growth to a rapid growth, while the peak-to-peak value of the anode current exhibits a non-monotonic behavior. A preliminary analysis shows that the asymmetrical distribution of the propellant causes a nonuniform plasma generation along the azimuthal direction and consequently the appearance of an azimuthal electric field. The effect of the azimuthal electric field on the electron azimuthal drift as well as the induction of the electron axial drift are key factors that account for the change of the anode current and its oscillation. 相似文献
16.
M. E. Burgos 《Foundations of Physics》2008,38(10):883-907
We present three different derivations of the transition probabilities to the continuum. It is shown that calculations, performed
as a direct application of the postulates of orthodox quantum mechanics (OQM), do not yield results consistent with experiments.
Traditional treatments are summarized and criticized. The relation of the transitions to the continuum with the traditional
quantum measurement problem is pointed out; we sum up and comment some contributions concerning this issue. It is shown that
an approach based on the notion of spontaneous projections yields expressions of the transition probabilities similar to those
obtained in the traditional way and new predictions which could be submitted to experimental tests. 相似文献
17.
A gedanken experiment that distinguishes locally between acceleration of rotation and linear acceleration is described and
discussed. 相似文献
18.
Considering external electric field as well as third- and fourth-order phonon anharmonic interaction terms in the pseudospin-lattice
coupled mode (PLCM) model Hamiltonian for KDP-type ferroelectrics, expressions for field-dependent shift, width, renormalized
soft mode frequency, Curie temperature, dielectric constant and dielectric loss are evaluated. For the calculation, method
of statistical double-time temperature-dependent Green’s function has been used. By fitting model values of physical quantities,
temperature and electric field dependences of soft mode frequency, dielectric constant and loss have been calculated which
compare well with experimental results of Baumgartner [8] and Choi and Lockwood [9]. Both dielectric constant and loss decrease
with electric field. 相似文献
19.
Amitabha Ghosh 《Pramana》1986,26(1):1-8
According to the model of inertial induction proposed earlier, the inertia force consists of an acceleration-dependent term
which comes out as identically equal to -ma. Besides, there is a velocity-dependent term which is exceedingly small to be easily detected. However, it has been shown
that this results in a cosmological red shift of light coming from distant stars and galaxies; the magnitude of the red shift
agrees very well with the observed values. Though this model yields correct results when applied to photons it needs modification
before applying to other bodies. A modified form of the inertial induction model is now proposed where the proposed velocity-dependent
inertia forces, when applied to the solar system, yields correct order of magnitude for the secular retardation of the earth’s
rotation. Moreover, a combined model using the velocity term and the tidal friction also does not suggest any close proximity
of the moon to the earth in the past. When the model is applied to the case of Phobos, a secular acceleration of the order
of magnitude of 10−3 deg yr−2 is obtained. 相似文献