Effect of Magnetic Field on the Momentum Relaxation Rate of Charge Carriers in a Size-Quantized Wire

2005 ◽  
Vol 277-279 ◽  
pp. 881-885
Author(s):  
Sh.G. Gasparyan
Keyword(s):  
Magnetic Field ◽  
Relaxation Rate ◽  
Surrounding Medium ◽  
Impurity Scattering ◽  
Dielectric Constants ◽  
Charge Carriers ◽  
Wire Radius ◽  
Inhomogeneity Parameter ◽  
Momentum Relaxation ◽  
The Wire

The effect of a longitudinal magnetic field and the dielectric constants mismatch of a size- quantized wire and surrounding medium on the impurity scattering of charge carriers is considered. The expressions for the momentum relaxation rate are carried out for scattering on charged Coulomb centers located on the wire axis. The dependences of the momentum relaxation rate on the magnetic field induction, dielectric inhomogeneity parameter, and also on the wire radius are obtained.

DEPHASING IN PRESENCE OF A MAGNETIC FIELD

2007 ◽  
Vol 06 (03n04) ◽  
pp. 261-264 ◽  
Author(s):  
A. V. GERMANENKO ◽  
V. A. LARIONOVA ◽  
I. V. GORNYI ◽  
G. M. MINKOV
Keyword(s):  
Magnetic Field ◽  
Relaxation Time ◽  
Relaxation Rate ◽  
Negative Magnetoresistance ◽  
Phase Relaxation ◽  
Quasi Momentum ◽  
Fitting Procedure ◽  
Electron Interference ◽  
Momentum Relaxation ◽  
The Magnetic Field

Effect of the magnetic field on the rate of phase breaking is studied. It is shown that the magnetic field resulting in the decrease of phase relaxation rate [Formula: see text] makes the negative magnetoresistance due to suppression of the electron interference to be smoother in shape and lower in magnitude than that found with constant [Formula: see text]-value. Nevertheless our analysis shows that experimental magnetoconductance curves can be well fitted by the Hikami–Larkin–Nagaoka expression.1 The fitting procedure gives the value of τ/τϕ, where τ is the quasi-momentum relaxation time, which is close to the value of τ/τϕ(B = 0) with an accuracy of 25% or better when the temperature varies within the range from 0.4 to 10 K. The value of the prefactor α found from this procedure lies within the interval 0.9–1.2.

scholarly journals Dynamics of Ion Channels via Non-Hermitian Quantum Mechanics

Entropy ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 125
Author(s):  
Tobias Gulden ◽  
Alex Kamenev
Keyword(s):  
Quantum Mechanics ◽  
Algebraic Topology ◽  
Riemann Surfaces ◽  
Surrounding Medium ◽  
Coulomb Systems ◽  
Dielectric Constants ◽  
Ion Interactions ◽  
Multivalent Ions ◽  
Electric Filed ◽  
Entropic Effects

We study dynamics and thermodynamics of ion transport in narrow, water-filled channels, considered as effective 1D Coulomb systems. The long range nature of the inter-ion interactions comes about due to the dielectric constants mismatch between the water and the surrounding medium, confining the electric filed to stay mostly within the water-filled channel. Statistical mechanics of such Coulomb systems is dominated by entropic effects which may be accurately accounted for by mapping onto an effective quantum mechanics. In presence of multivalent ions the corresponding quantum mechanics appears to be non-Hermitian. In this review we discuss a framework for semiclassical calculations for the effective non-Hermitian Hamiltonians. Non-Hermiticity elevates WKB action integrals from the real line to closed cycles on a complex Riemann surfaces where direct calculations are not attainable. We circumvent this issue by applying tools from algebraic topology, such as the Picard-Fuchs equation. We discuss how its solutions relate to the thermodynamics and correlation functions of multivalent solutions within narrow, water-filled channels.

scholarly journals Interaction of an electromagnetic E-wave with a thin conducting film between two dielectric media in the case of an anisotropic isoenergetic surface and impurity scattering

2021 ◽  
Vol 2103 (1) ◽  
pp. 012156
Author(s):  
I A Kuznetsova ◽  
D N Romanov ◽  
A A Yushkanov
Keyword(s):  
Impurity Scattering ◽  
Charge Carriers ◽  
Surface Scattering ◽  
Conducting Film ◽  
Dielectric Media ◽  
Thin Conducting ◽  
Transmission And Absorption ◽  
Thin Conducting Film ◽  
The Magnetic Field ◽  
Isoenergetic Surface

Abstract The coefficients of reflection, transmission and absorption are calculated in the framework of the kinetic approach, when an electromagnetic E-wave interacts with a thin conducting film located between two dielectric media. To account for the surface scattering of charge carriers is used a model of mirror-diffuse boundary conditions, assuming that the specularity coefficients of the upper and lower surfaces of the film differ from each other. The electromagnetic wave falls on the upper surface of the film at an arbitrary angle. The case of an anisotropic isoenergetic surface of a conductor having the form of a three-axis ellipsoid, one of the main axes of which is parallel to the magnetic field strength of the wave, and the other is perpendicular to the film surfaces, is considered. The impurity scattering of electrons (holes) is dominated in the volume of the conductor. The dependence of the absorption coefficient on the parameters of the isoenergetic surface of the conductor is analyzed.

scholarly journals XMM-Newton and Geminga

2004 ◽  
Vol 218 ◽  
pp. 215-218
Author(s):  
Patrizia Caraveo ◽  
Andrea De Luca ◽  
Sandro Mereghetti ◽  
Alberto Pellizzoni ◽  
Giovanni Bignami ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Surrounding Medium ◽  
Matter Density ◽  
Bow Shock ◽  
Synchrotron Emission ◽  
Electron Synchrotron ◽  
X Ray ◽  
Injection Energy ◽  
Pulsar Wind ◽  
Supersonic Motion

A deep XMM-Newton/EPIC observation of the field of the Geminga pulsar unveiled the presence of two elongated parallel X-ray tails trailing the neutron star. They are aligned with the object's supersonic motion, extend for ∼ 2′, and have a nonthermal spectrum produced by electron-synchrotron emission in the bow shock between the pulsar wind and the surrounding medium. Such a first ever X-ray detection of a pulsar bow shock allows us to gauge the pulsar electron injection energy and the shock magnetic field while constraining the angle of Geminga's motion and the local matter density.

scholarly journals Magnetic field influenced electron-impurity scattering and magnetotransport

2019 ◽  
Vol 100 (13) ◽  
Author(s):  
Jingjing Feng ◽  
Cong Xiao ◽  
Yang Gao ◽  
Qian Niu
Keyword(s):  
Magnetic Field ◽  
Impurity Scattering

scholarly journals Parallel Simulation of HGMS of Weakly Magnetic Nanoparticles in Irrotational Flow of Inviscid Fluid

2014 ◽  
Vol 2014 ◽  
pp. 1-12
Author(s):  
Kanok Hournkumnuard ◽  
Banpot Dolwithayakul ◽  
Chantana Chantrapornchai
Keyword(s):  
Magnetic Nanoparticles ◽  
Particle Transport ◽  
Parallel Simulation ◽  
Outer Radius ◽  
Inviscid Fluid ◽  
Wire Radius ◽  
Problem Size ◽  
Irrotational Flow ◽  
The Wire ◽  
Weakly Magnetic

The process of high gradient magnetic separation (HGMS) using a microferromagnetic wire for capturing weakly magnetic nanoparticles in the irrotational flow of inviscid fluid is simulated by using parallel algorithm developed based on openMP. The two-dimensional problem of particle transport under the influences of magnetic force and fluid flow is considered in an annular domain surrounding the wire with inner radius equal to that of the wire and outer radius equal to various multiples of wire radius. The differential equations governing particle transport are solved numerically as an initial and boundary values problem by using the finite-difference method. Concentration distribution of the particles around the wire is investigated and compared with some previously reported results and shows the good agreement between them. The results show the feasibility of accumulating weakly magnetic nanoparticles in specific regions on the wire surface which is useful for applications in biomedical and environmental works. The speedup of parallel simulation ranges from 1.8 to 21 depending on the number of threads and the domain problem size as well as the number of iterations. With the nature of computing in the application and current multicore technology, it is observed that 4–8 threads are sufficient to obtain the optimized speedup.

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