Matter in superstrong magnetic fields

1986 ◽  
Vol 64 (3) ◽  
pp. 256-268 ◽  
Author(s):  
J. E. Skjervold ◽  
E. Østgaard
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Variational Method ◽  
Cohesive Energy ◽  
Condensed Matter ◽  
Binding Energies ◽  
Free Atoms ◽  
The Difference ◽  
Cohesive Energies

The behaviour of condensed matter in superstrong magnetic fields of the order of 1012–1015 G is investigated, i.e., binding energies of atoms in condensed matter are calculated by a variational method. The cohesive energy, i.e., the difference between the binding energies of free atoms and of atoms in condensed matter, is also calculated, and results are obtained for hydrogen, helium, carbon, oxygen, silicon, and iron atoms.For a magnetic field of 1012 G, we obtain binding energies for atoms in condensed matter of 0.2 keV for hydrogen, 0.7 keV for helium, 4.5 keV for carbon, 7.4 keV for oxygen, 20.0 keV for silicon, and 59.0 keV for iron. For a magnetic field of 1014 G, we get corresponding binding energies of 1.2 keV for hydrogen, 3.9 keV for helium, 27.0 keV for carbon, 44.9 keV for oxygen, 121.5 keV for silicon, and 366 keV for iron. For a magnetic field of 1012 G, we obtain cohesive energies of 0.04 keV for hydrogen, 0.10 keV for helium, 0.36 keV for carbon, 0.51 keV for oxygen, 1.4 keV for silicon, and 2.8 keV for iron. For a magnetic field of 1014 G, we get corresponding cohesive energies of 0.16 keV for hydrogen, 0.40 keV for helium, 1.9 keV for carbon, 3.0 keV for oxygen, 7.3 keV for silicon, and 19.4 keV for iron.

TWO-DIMENSIONAL D- DONOR IN A STRONG MAGNETIC FIELD

2008 ◽  
Vol 22 (26) ◽  
pp. 2579-2585
Author(s):  
XIAOYAN ZHANG ◽  
GUOLIANG FAN ◽  
JINFENG WANG
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Variational Method ◽  
Bound State ◽  
Binding Energies ◽  
Triplet States ◽  
Two Dimensional ◽  
Threshold Values ◽  
Spin Triplet ◽  
The Magnetic Field

Two-dimensional negative donor ion in magnetic fields are investigated. Using a variational method, we calculated the binding energies of D- center for the spin-triplet states of L = -2 and L = -3 in this structure. The threshold values of the magnetic field which turn unbound state into bound state were obtained.

Effect of Magnetic Fields on the Resistance and Microstructure of Al-Cu Alloy during Solidification Processing

2011 ◽  
Vol 287-290 ◽  
pp. 2916-2920
Author(s):  
Chun Yan Ban ◽  
Peng Qian ◽  
Xu Zhang ◽  
Qi Xian Ba ◽  
Jian Zhong Cui
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Turning Points ◽  
Probe Method ◽  
Solidification Processing ◽  
Ac Magnetic Field ◽  
Dc Magnetic Field ◽  
Cu Alloy ◽  
The Difference ◽  
Good Agreement

The resistance of Al-21%Cu alloy under no magnetic field, DC magnetic field and AC magnetic field from liquid to solid was measured by a four-probe method. The difference of resistance versus temperature curves (R-T curves) was analyzed. It is found that the R-T curves of Al-21%Cu alloy are monotone decreasing and have two obvious turning points. Under DC magnetic field, the liquidus and solidus temperatures of the alloy both decrease, while under AC magnetic field, the liquidus and solidus temperatures both increase. There is a good agreement between the microstructure of quenching sample and R-T curves. The mechanism of the effect of magnetic fields was discussed.

Magneto-Spectroscopy of Two-Electron Transitions in Homoepitaxial GaN.

2001 ◽  
Vol 693 ◽  
Author(s):  
M. Wojdak ◽  
J.M. Baranowski ◽  
A. Wysmolck ◽  
K. Pakula ◽  
R. Stepnicwski ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Excited State ◽  
Magnetic Fields ◽  
Effective Mass ◽  
Electron Energy ◽  
Electron Transition ◽  
Electron Effective Mass ◽  
Neutral Donor ◽  
Electron Transitions ◽  
The Difference

AbstractTwo-electron transition occurs when the exciton bound to a neutral donor (DBE) recombines and leaves the donor in an excited state. The two-electron energy is therefore lower than that of the DBE peak by the difference in ground and excited state of the neutral donor. In a magnetic field the two-electron satellite splits into several components. These intra-donor excitations have been studied in homoepitaxial GaN up to magnetic fields reaching 23T. For Faraday (B‖c) configuration the two-electron transition splits mainly into 2s, 2p0, 2p+ and 2p- components. The total splitting between 2p+ and 2p- is equal to Landau energy. For Voigt (B???c) configuration in addition to transition to 2s, 2p0, 2p- and 2p+ there are additional lines which origin is discussed. It has been found that for two configurations of magnetic field the separation between 2p+ and 2p- is not exactly equal, what indicates the anisotropy of the electron effective mass. It has been found that m| = 0.205m0 and m??? = 0.225m0.

scholarly journals Strongly Magnetized Sources: QED and X-ray Polarization

Galaxies ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 76 ◽  
Author(s):  
Jeremy Heyl ◽  
Ilaria Caiazzo
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
First Principles ◽  
Quantum Electrodynamics ◽  
Polarization State ◽  
Radiative Corrections ◽  
Strong Magnetic Fields ◽  
X Ray ◽  
The Difference

Radiative corrections of quantum electrodynamics cause a vacuum threaded by a magnetic field to be birefringent. This means that radiation of different polarizations travels at different speeds. Even in the strong magnetic fields of astrophysical sources, the difference in speed is small. However, it has profound consequences for the extent of polarization expected from strongly magnetized sources. We demonstrate how the birefringence arises from first principles, show how birefringence affects the polarization state of radiation and present recent calculations for the expected polarization from magnetars and X-ray pulsars.

Study on the Solidification Structures of Al-Fe-Si Alloy under DC and AC Magnetic Fields

2011 ◽  
Vol 189-193 ◽  
pp. 4477-4482
Author(s):  
Chun Yan Ban ◽  
Xu Zhang ◽  
Peng Qian ◽  
Yi Han ◽  
Jian Zhong Cui
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Chinese Script ◽  
Minor Amount ◽  
Fine Needle ◽  
Ac Magnetic Field ◽  
Dc Magnetic Field ◽  
Conventional Condition ◽  
The Difference ◽  
Al Matrix

The effects of DC and AC magnetic field on the phase composition, morphology and distribution of the ternary Al-Fe-Si alloy were investigated. The solidification structures of the alloy solidified with and without the application of magnetic fields were confirmed by DSC and structural measurements. The results showed that, in this Al-Fe-Si alloy the fine needle-like Al3Fe phase dominated the microstructure at the grain boundaries with the minor amount of Chinese script-like α-AlFeSi. Distribution of Al3Fe phase was almost homogeneous in the volume of the sample when alloy was solidified in the conventional condition. When the DC magnetic field was imposed, distribution of Al3Fe phase was more homogeneous. However, the Al3Fe and α-AlFeSi phases were accumulated towards the center of the sample with the application of the AC magnetic field. This is due to the difference of Lorentz force between Al matrix and iron-containing intermetallics. Furthermore, the amount of Chinese script-like α-AlFeSi was increased remarkably under AC magnetic field.

POLARON CORRECTION TO THE NEGATIVE DONOR ON THE HETERO-INTERFACE IN MAGNETIC FIELDS (II–VI CRYSTALS)

2003 ◽  
Vol 17 (31n32) ◽  
pp. 6097-6107 ◽  
Author(s):  
XIAOYAN ZHANG ◽  
XU WANG ◽  
GUOLIANG FAN
Keyword(s):  
Magnetic Fields ◽  
Variational Method ◽  
Triplet State ◽  
Numerical Results ◽  
Binding Energies ◽  
Phonon Coupling ◽  
Polar Crystal ◽  
Spin Triplet

Negative donor ion on the hetero-interface in magnetic fields are investigated. Using a variational method, we have calculated the binding energies of D- center for the spin-triplet state of L=-1 in this structure. Moreover, the effect of electron-interface phonon coupling on the energy of a donor located in a polar-crystal hetero-interface is found. Numerical results are produced for heterostructures of some II–VI crystals.

scholarly journals SUTHERLAND-EINSTEIN HYPOTHESIS ON THE ORIGIN OF MAGNETIC FIELDS IN ASTROPHYSICAL OBJECTS

Metaphysics ◽  
2020 ◽  
pp. 166-174
Author(s):  
I. A Babenko
Keyword(s):  
Magnetic Field ◽  
Twentieth Century ◽  
Magnetic Fields ◽  
Field Experiments ◽  
The Earth ◽  
Astrophysical Objects ◽  
The Difference ◽  
Rotation Of The Earth

The article discusses the theoretical and experimental foundations of the hypothesis on the origin the magnetic field's the Earth's and other astrophysical objects, put forward at the beginning of the twentieth century by Sutherland and Einstein. According to this hypothesis, the different of the electric charg of the electron and proton and the rotation of the Earth (astronomical), leads to the appearance of a magnetic field. Experiments under terrestrial conditions aimed at determining the difference between the electric charges of an electron and a proton are discussed.

scholarly journals Occupational Exposure to Steady Magnetic Fields and Mental Health of workers at the Copper Electrolysis Unit

2015 ◽  
Vol 1 (2) ◽  
pp. 1 ◽  
Author(s):  
Mohammad Reza Ghotbi ◽  
Hossein Mardi ◽  
Narges Khanjani ◽  
Nooshin Parvaresh
Keyword(s):  
Magnetic Field ◽  
Mental Health ◽  
Magnetic Fields ◽  
General Health Questionnaire ◽  
Exposed Group ◽  
Chi Square ◽  
Cross Sectional ◽  
Steady Magnetic Field ◽  
The Mean ◽  
The Difference

<p><strong>Background: </strong>There are a few studies about the health effects of steady magnetic fields. This study was performed in order to evaluate some of the mental effects of exposure to steady magnetic fields in the copper electrolysis unit.<strong></strong></p><p><strong>Methods: </strong>This cross-sectional descriptive and analytical study was performed at the electrolysis unit of a Copper Complex in Kerman Province in 2013. The populations under study were ninety workers exposed to steady magnetic fields chosen as the exposed group and 90 workers without exposure chosen from the concentration unit and similar to the exposure group in regard to working conditions. The intensity of steady magnetic field was measured in different parts of the saloon and in the head, waist and feet position. Measuring mental signs was performed by the General Health Questionnaire GHQ-28. Data analysis was performed through SPSS19 and the Mann-Whitney U, one way ANOVA, Chi-square test and Regression analysis was used.</p><p><strong>Results: </strong>In this study the mean intensity of the steady magnetic field in the exposed group was 2.5 mT. The mean rank of mental health in the exposed group was 102.04 and in the unexposed group was 78.96 and the difference was statistically significant (p=0.003). Also there were statistical differences between the two groups in anxiety and sleep disorder (p=0.001) and depression (p=0.007) dimensions.</p><p><strong>Conclusion: </strong>It appears that exposure to static magnetic fields can cause psychological complications. Therefore, more research is recommended to improve the safety of workers exposed to these fields.<strong></strong></p>

scholarly journals 22. On the magnetic fields of novae and super-novae

1958 ◽  
Vol 6 ◽  
pp. 193-203 ◽  
Author(s):  
E. R. Mustel
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
General Magnetic Field ◽  
The Difference ◽  
Light Maximum

This paper is a development of the hypothesis, suggested earlier by the author, namely that novae possess a large general magnetic field. This hypothesis explains the following facts: (a) effects of the retardation of matter in novae before light maximum, (b) a preferential ejection of matter from novae in two diametrically opposite directions during an outburst, and (c) formation of rings and equatorial belts after light maximum, observed in N Aql 1918 and N Her 1934. These rings and belts are formed due to the fact that the general magnetic field of new stars deflects condensations of continuous ejection (the diffuse-enhanced and Orion spectra) towards the equator.Magnetic fields inside novae must be ‘tangled’. This explains (a), as well as the difference between cases (b) and (c).The structure of envelopes, ejected by novae, must reflect the presence of tangled magnetic fields. According to G. A. Shajn this is confirmed for super-novae, the envelopes of which may be studied in detail.

Sign in / Sign up

Export Citation Format

Share Document