The effect of periodic magnetic field on the fabrication and field …
The magnetic field is an important non-contacting energy field that can affect material synthesis. In this study, a dynamic magnetic field with an angular frequency of 100 π rad/s was applied in hot filament chemical vapor deposition, and its effects on diamond nucleation were intensively investigated by scanning electron microscopy, …
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Electron band structure in a two-dimensional periodic magnetic field
In this paper we study the energy spectrum of a two-dimensional electron gas (2DEG) in a two-dimensional periodic magnetic field. Both a square magnetic lattice and a triangular one are considered. We consider the general case where the magnetic field in a cell can be of any shape. A general feature of the band structure is …
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What causes the periodic reversals of the earth's magnetic field…
"The dipole part of the field is usually aligned fairly closely with the Earth's rotation axis; in other words, the magnetic poles are usually fairly close to the geographic poles, which is why a ...
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Magnetic Susceptibility
Magnetic susceptibility is a measure of the ability of a substance to be magnetized in the presence of an external magnetic field. In principle, magnetic susceptibility …
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Unified wrench model of an ironless permanent magnet planar motor …
In this paper, a unified wrench model (UWM) in the two-dimensional (2D) periodic magnetic field is proposed by analysing the integral terms of the Lorentz force. It is available for coils with arbitrary shapes and arbitrary orientations. It gives the general form of the wrench excited by all the harmonic components of the magnetic field.
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Giant magnetoresistance and possible miniband effects in periodic …
We have investigated the magnetoresistance (MR) of high mobility, near surface two-dimensional electron gases that are subject to a periodic magnetic field of amplitude up to 0.3 T. The fields are produced by sub-micron arrays of ferromagnetic stripes on the surface of the heterostructures. For small applied external magnetic fields …
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Magnetic Survey
A magnetic survey is one of the exploration tools used for measuring localized changes in the Earth's magnetic field, caused by sedimentary rocks or mineral ore bodies. The …
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Giant magnetoresistance and possible miniband …
We have investigated the magnetoresistance (MR) of high mobility, near surface two-dimensional electron gases that are subject to a periodic magnetic field of …
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Improvement of unidirectional focusing periodic
Since the permanent magnet has a thickness h, in order to simplify the analysis process, the center of the lower surface of the permanent magnet can be regarded as the rotation axis.Then an angled bias magnetic field varies with the increase in the rotation angle φ of the periodic permanent magnet. Since the eddy current on the …
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A New Method to Focus SEBs Using the Periodic …
Kobe 6500023, Japan; dazhi_li@hotmail. Abstract: In this paper, a novel method, named PM-E, to focus the sheet electron beam (SEB) is proposed. This new method consists of a periodic magnetic field and an electrostatic field, which are used to control the thickness and width of the SEB, respectively.
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Electrons in a periodic magnetic field
The miniband Aharonov-Bohm oscillations and the interminiband absorption coefficient have been considered theoretically for one-layer superlattices of square and rectangular symmetries, composed of cylindrical quantum rings in the external transverse magnetic field with a periodic vector potential by the lattice constants.
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Two-dimensional electron gas in a periodic magnetic …
We study the energy spectrum and electronic properties of a two-dimensional (2D) spinless electron gas in a periodic magnetic field which has the …
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Periodic magnetic modulation enhanced electrochemical …
Setup of the periodic magnetic field modulation prototype. Periodic movement of MBs was controlled by the external magnetic field with switchable features, alternately generated by a pair of strong neodymium disc magnets (diameter 6 mm × thick 0.8 mm, Magpanda Science and Technology Ltd., Ningbo, China).
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3.7: Magnetism
3.80 Magnetite. Magnetism derives from a property called the magnetic moment that results from the spinning and orbiting of electrons. The sum of all the magnetic moments of all the atoms in a …
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Phys. Rev. E 80, 026314 (2009)
We have investigated the influence of a time-periodic and spatially homogeneous magnetic field on the linear stability properties and on the nonlinear response of a ferrofluid layer heated from below and from above. A competition between stabilizing thermal and viscous diffusion and destabilizing buoyancy and Kelvin forces …
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PERIODIC AHARONOV–BOHM SOLENOIDS IN A CONSTANT MAGNETIC FIELD
We consider the magnetic Schrodinger operator on R2. The magnetic field is the sum of a homogeneous magnetic field and periodically varying pointlike magnetic fields on a lattice. We shall give a sufficient condition for each Landau level to be an infinitely degenerated eigenvalue. This condition is also necessary for the lowest Landau …
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21.4: Motion of a Charged Particle in a Magnetic Field
A further difference between magnetic and electric forces is that magnetic fields do not net work, since the particle motion is circular and therefore ends up in the same place. We express this mathematically as: W = ∮B ⋅ dr = 0 (21.4.5) (21.4.5) W = ∮ B ⋅ d r = 0.
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Large-area, periodic, and tunable intrinsic pseudo-magnetic fields …
Here, the authors report experimental tuning of large area periodic pseudo-magnetic fields within twisted bilayer graphene and massive Dirac electrons having circularly localized pseudo-Landau levels.
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Simulation and experimental study of short-period strong magnetic field …
The dimensions of the magnet blocks and the poles are numerically optimized for a sample undulator with a period length of 16 mm and a gap of 5 mm. Compared to the conventional hybrid undulator, the effective peak field can be enhanced by about 48%. An eight-period model is built and the result of the magnetic field …
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21.1: Magnetism and Magnetic Fields
These effects can be combined into a partial differential equation called the magnetic induction equation: ∂B ∂t = η∇2B +∇ × (u ×B) (21.1.7) (21.1.7) ∂ B ∂ t = η ∇ 2 B + ∇ × ( u × B) In this equation u is the velocity of the fluid, B is the magnetic field, and eta is the magnetic diffusivity. The first term on the right ...
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A New Method to Focus SEBs Using the Periodic …
In this paper, a novel method, named PM-E, to focus the sheet electron beam (SEB) is proposed. This new method consists of a …
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[2208.10516] Dirac electron under periodic magnetic field: …
View a PDF of the paper titled Dirac electron under periodic magnetic field: Platform for fractional Chern insulator and generalized Wigner crystal, by Junkai Dong and 2 other authors
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Efficient removal of uranium from acidic mining wastewater …
Recycling the magnetic phosphate composite with an external magnetic field is a rapid and straightforward process. However, the effectiveness of recycling after recovery largely depends on the choice of desorption agent. CaFeP-1 interacts effectively with strong acids such as HNO 3, optimizing the desorption rate of uranium (Fig. 10 (A ...
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Ground states of a two-dimensional electron in a …
premises to the important case of a periodic field, i. e., to find all the ground states for a two-dimension- al Pauli operator in a periodic magnetic field directed along the z axis; the number of ground states turned out to be "the same" as in a uniform field with the same flux. This means that the degeneracy of the
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The effect of periodic magnetic field on the …
Periodic magnetic field was used to deposit nano-diamond film. •. Magnetic field angular frequency has influence on nano-diamond preparation. •. High …
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Modification of polycrystalline nanodiamonds by using periodic magnetic …
Here, we report a new approach to the modification of nanodiamonds by periodic magnetic field (PMF) enhanced hydrogen plasma. The rotating magnetic field can improve the spatial distribution of hydrogen plasma and keep charged particles in the plasma away from the vacuum chamber wall [13] .
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Electrons in a periodic magnetic field
Abstract. The properties of a two-dimensional electron gas (2DEG) under the influence of a perpendicular magnetic field which is periodic in one direction are investigated. Two situations are considered: (i) a periodic array of magnetic field steps, and (ii) a saw-tooth magnetic field profile. In contrast with the usual potential-modulated …
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Structure and magnetic field of periodic permanent magnetic focusing
Research highlights For open magnetic rings, both calculated and measured results show that the existence of the radial magnetic field creates a remarkable cosine distribution field along the central axis. A new structure of periodic permanent magnet (PPM) focusing system with open magnetic rings is proposed. The new PPM focusing …
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Magnetite | Common Minerals
Magnetite is a black, opaque, magnetic mineral that leaves a black streak when rubbed across a hard rough surface. It is one of the most abundant metal oxides, and its crystal structure contains both the ferrous (Fe+2) and ferric (Fe+3) forms of iron ions. A complex pattern of electrons between the two forms of iron is the source of its ...
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Magnetic Survey
Magnetic Survey - Mining Fundamentals. A magnetic survey is one of the exploration tools used for measuring localized changes in the Earth's magnetic field, caused by sedimentary rocks or mineral ore bodies. The magnetic properties of mineral ore bodies and igneous rocks allow them to be easily identified and mapped, via magnetic surveys.
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