The c-axis fluctuation conductivity in layered superconductors in a strong electric field under a magnetic field

ABSTRACT We present a model for fast radio bursts (FRBs) where a large-amplitude Alfvén wave packet is launched by a disturbance near the surface of a magnetar, and a substantial fraction of the wave energy is converted to coherent radio waves at a distance of a few tens of neutron star radii. The wave amplitude at the magnetar surface should be about 1011 G in order to produce an FRB of isotropic luminosity 1044 erg s−1. An electric current along the static magnetic field is required by Alfvén waves with non-zero component of transverse wave vector. The current is supplied by counter-streaming electron–positron pairs, which have to move at nearly the speed of light at larger radii as the plasma density decreases with distance from the magnetar surface. The counter-streaming pairs are subject to two-stream instability, which leads to formation of particle bunches of size of the order of c/ωp, where ωp is the plasma frequency. A strong electric field develops along the static magnetic field when the wave packet arrives at a radius where electron–positron density is insufficient to supply the current required by the wave. The electric field accelerates particle bunches along the curved magnetic field lines, and that produces the coherent FRB radiation. We provide a number of predictions of this model.

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A Magnetoelectric Effect in Low-Carrier Density Colossal Magnetoresistance Materials

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.52.21 ◽

2006 ◽

Vol 52 ◽

pp. 21-26

Author(s):

M. Auslender

Keyword(s):

Magnetic Field ◽

Solid State ◽

Electric Field ◽

Acoustic Waves ◽

Carrier Density ◽

Colossal Magnetoresistance ◽

Magnetoelectric Effect ◽

Strong Electric Field ◽

Acoustoelectric Effect ◽

Dc Electric Field

It is shown that in colossal magnetoresistance materials an inhomogeneous alternating magnetic field generates a strong electric field of non-inductive nature. This magnetoelectric effect is an analog of acoustoelectric effect in conventional semiconductors. Due to the above electric field spin waves in the former materials, like acoustic waves in the latter ones, acquire an additional attenuation at equilibrium. This attenuation may be converted to amplification by applying strong enough dc electric field drifting the carriers (solid-state Cherenkov’s effect). The experiments, which probed this phenomenon in HgCr2Se4 using spin wave pumping, are discussed.

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Spherical neutron polarimetry in multiferroics under external stimuli

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314098489 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C151-C151

Author(s):

Vladimir Hutanu ◽

Andrew Sazonov ◽

Georg Roth ◽

In-Hwan Oh ◽

Max Baum ◽

...

Keyword(s):

Magnetic Field ◽

Electric Field ◽

Magnetic Structure ◽

Magnetic Order ◽

Strong Electric Field ◽

Electric Polarization ◽

Square Lattice ◽

Microscopic Mechanism ◽

Coupling Energy ◽

Neutron Polarimetry

Study of multiferroics, materials simultaneously having more than one primary ferroic order parameter, is a hot topic of material sciences. The most extensively studied class of these compounds is the family of magnetoelectric multiferroics, where ferroelectricity can be induced by various types of magnetic orderings via the relativistic spin-orbit interaction. As a consequence of the cross coupling between spins and electric polarization, the spectacular control of the ferroelectric polarization by external magnetic field and the manipulation of the magnetic order via electric field can often be realized in these systems. Depending on the symmetry and microscopic mechanism of the multiferroicity the coupling energy between magnetic and electric ordering parameters can significantly vary. Classical neutron diffraction often fails in the precise determining of the complex magnetic structure in the multiferroics due to the presence of the statistically distributed domains in the macroscopic sample. Using spherical neutron polarimetry (SNP), known also as 3D polarization analysis, it is possible not only to precisely determine the complex magnetic structure, but also to investigate in-situ its evolution with external parameters and to control the magnetic domains distribution under the influence of the external electric or/and magnetic field. Here we will present some SNP results on few different multiferroic materials. In some of them, e.g. square lattice 2D antiferromagnet Ba2CoGe2O7, even strong electric field does not change the magnetic order. However rater week magnetic field is sufficient to create a mono-domain structure and to rotate spins in the plane. In other e.g. incommensurate (spiral) magnetic structure of the TbMnO3, solely electric field is sufficient to fully control the chirality of the magnetic structure. In the case of Cr2O3 both electric and magnetic fields should be applied in parallel in order to switch between the different antiferromagnetic domains.

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ABLATION OF SOLID HYDROGEN IN CONTACT WITH MAGNETIZED PLASMAS : CAN THE EXTERNAL MAGNETIC FIELD BE THE UPPER LIMIT OF THE SELF CONSISTENT ELECTRIC FIELD AT THE SOLID SURFACE ?

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19797217 ◽

1979 ◽

Vol 40 (C7) ◽

pp. C7-447-C7-448

Author(s):

S. Mercurio

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Electric Field ◽

Solid Surface ◽

Solid Hydrogen ◽

The Self ◽

Magnetized Plasmas ◽

Upper Limit ◽

Self Consistent

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PEMANFAATAN RADIASI ENERGI TEGANGAN 150 KV UNTUK LAMPU LED PENERANGAN JALAN

Jurnal Teknik ◽

10.31000/jt.v7i1.936 ◽

2018 ◽

Vol 7 (1) ◽

Author(s):

Mauludi Manfaluthy

Keyword(s):

Magnetic Field ◽

Electric Field ◽

High Voltage ◽

Low Frequency ◽

Energy Utilization ◽

World Health ◽

Electromagnetic Signals ◽

Health Organization ◽

The Magnetic Field ◽

Low Frequency Waves

WHO (World Health Organization) concludes that not much effect is caused by electric field up to 20 kV / m in humans. WHO standard also mentions that humans will not be affected by the magnetic field under 100 micro tesla and that the electric field will affect the human body with a maximum standard of 5,000 volts per meter. In this study did not discuss about the effect of high voltage radiation SUTT (High Voltage Air Channel) with human health. The research will focus on energy utilization of SUTT radiation. The combination of electric field and magnetic field on SUTT (70-150KV) can generate electromagnetic (EM) and radiation waves, which are expected to be converted to turn on street lights around the location of high voltage areas or into other forms. The design of this prototype works like an antenna in general that captures electromagnetic signals and converts them into AC waves. With a capacitor that can store the potential energy of AC and Schottky diode waves created specifically for low frequency waves, make the current into one direction (DC). From the research results obtained the current generated from the radiation is very small even though the voltage is big enough.Keywords : Radiance Energy, Joule Thief, and LED Module.

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