THE MILLIMETRE-WAVE MAGNETO-OPTICAL RESPONSE OF Sr2RuO4

2002 ◽  
Vol 16 (20n22) ◽  
pp. 3238-3243
Author(s):  
A. ARDAVAN ◽  
E. RZEPNIEWSKI ◽  
R. S. EDWARDS ◽  
J. SINGLETON ◽  
Y. MAENO
Keyword(s):  
Magnetic Field ◽  
Fermi Surface ◽  
Effective Mass ◽  
Cyclotron Resonance ◽  
P Wave ◽  
Harmonic Series ◽  
Millimetre Wave ◽  
The Magnetic Field ◽  
Component Parallel ◽  
Absorption Mode

We report a study of the angle-dependent millimetre-wave magnetoconductivity of the p-wave triplet-paired perovskite superconductor Sr 2 RuO 4. We find two harmonic series. We assign the first to interlayer cyclotron resonance of the β-Fermi surface and its harmonics, yielding a cyclotron effective mass of [Formula: see text]. We assign the second series, which contains only odd harmonics, to cyclotron resonance of the γ-Fermi surface, yielding a cyclotron effective mass of [Formula: see text]. In addition, we find a very strong absorption mode in the presence of a magnetic field component parallel to the quasi-two-dimensional (Q2D) planes of the sample. Its dependence on the orientation of the magnetic field cannot be described in the context of conventional Q2D cyclotron resonance, and the origin of this mode is not yet clear.

Tipping effects in Azbel-Kaner cyclotron resonance

1967 ◽  
Vol 297 (1449) ◽  
pp. 205-229 ◽  
Keyword(s):  
Magnetic Field ◽  
Fermi Surface ◽  
Cyclotron Resonance ◽  
Skin Depth ◽  
Electron Model ◽  
Line Shapes ◽  
Parallel Polarization ◽  
Free Electron Model ◽  
Set Up ◽  
The Magnetic Field

Calculations of Azbel-Kaner line shapes when the magnetic field is tipped out of the surface have been carried out in a number of cases for both the free electron model and an arbitrary Fermi surface with mass spread. For small angles of tip the results substantiate the Doppler shift theory advanced by Koch, Stradling & Kip and provide a consistent explanation of the observed peak shifts or splitting in all cases. Arguments are presented that at larger tip angles the overall absorption will decrease with increasing field, and the original resonance may become inverted, owing to the removal of non-stationary electrons from the skin depth. At large tip angles (5° or so) inverted and doubled resonances observed with parallel polarization are shown to arise from ‘field splashes’ set up by drifting electrons from the limiting points, regardless of the nature of the Fermi surface. Apparently normal resonances observed at very large tip angles are shown to arise from so-called ‘cylinder sections’ where d A /dk 2 H = 0 and v D = 0, A and v D being the area of the orbit in k space and the drift velocity respectively.

High Field Magnetoacoustic Investigation of the Fermi Surface of Tungsten

1973 ◽  
Vol 51 (1) ◽  
pp. 77-86 ◽  
Author(s):  
J. P. Kalejs ◽  
J. M. Perz
Keyword(s):  
Magnetic Field ◽  
Fermi Surface ◽  
Empirical Model ◽  
Cyclotron Resonance ◽  
High Field ◽  
Ultrasonic Waves ◽  
Quantum Oscillations ◽  
Resonance Data ◽  
The Magnetic Field ◽  
Longitudinal Ultrasonic Waves

We have measured the frequencies of quantum oscillations in the attenuation of 20 MHz longitudinal ultrasonic waves in tungsten in magnetic fields up to 109 kOe. Our results agree well with the de Haas–van Alphen (dHvA) data of Girvan, Gold, and Phillips (GGP). In addition, we see features predicted by the empirical model developed by GGP but not observed directly in the dHvA studies. Specifically, we find strong evidence of the continuation of the ω branch (GGP notation) for the magnetic field H in the [Formula: see text] plane right to the [110] direction; we also observe splitting of the ξ branch for field directions near [111], but not to the extent predicted by the model. From the temperature dependence of the amplitudes of the quantum oscillations, we have deduced cyclotron masses for some orbits; these agree well with GGP and cyclotron resonance data.

Dependence of the a-Si:H Defect Density of States on the Magnetic Field Profile of an Electron Cyclotron Resonance Microwave Plasma

1992 ◽  
Vol 258 ◽  
Author(s):  
F.S. Pool ◽  
J.M. Essick ◽  
Y.H. Shing ◽  
R.T. Mather
Keyword(s):  
Magnetic Field ◽  
Density Of States ◽  
Cyclotron Resonance ◽  
Electron Cyclotron Resonance ◽  
Microwave Plasma ◽  
Defect Density ◽  
Electron Cyclotron ◽  
Field Profile ◽  
Magnetic Field Profile ◽  
The Magnetic Field

ABSTRACTThe magnetic field profile of an electron cyclotron resonance (ECR) microwave plasma was systematically altered to determine subsequent effects on a-Si:H film quality. Films of a-Si:H were deposited at pressures of 0.7 mTorr and 5 mTorr with a H2/SiH4 ratio of approximately three. The mobility gap density of states ND, deposition rate and light to dark conductivity were determined for the a-Si:H films. This data was correlated to the magnetic field profile of the plasma, which was characterized by Langmuir probe measurements of the ion current density. By variation of the magnetic field profile ND could be altered by more than an order of magnitude, from 1×1016 to 1×1017 at 0.7 mTorr and 1×1016 to 5×1017 at 5 mTorr. Two deposition regimes were found to occur for the conditions of this study. Highly divergent magnetic fields resulted in poor quality a-Si:H, while for magnetic field profiles defining a more highly confined plasma, the a-Si:H was of device quality and relatively independent of the magnetic field configuration.

Cyclotron resonance in the extreme anomalous relaxation region

1964 ◽  
Vol 278 (1373) ◽  
pp. 256-273 ◽  
Keyword(s):  
Magnetic Field ◽  
Electron Scattering ◽  
Cyclotron Resonance ◽  
Surface Resistance ◽  
Electron Gas ◽  
Degenerate Semiconductors ◽  
Line Shapes ◽  
Infra Red ◽  
Anomalous Relaxation ◽  
The Magnetic Field

A reformulation of the theory of cyclotron resonance in metals as a variational problem is combined with the exact solution of the Boltzmann equation and used to calculate the surface resistance of an isotropic electron gas, in the extremeanom alous relaxation region, as a function of an applied magnetic field parallel to the surface of the medium . The line shapes obtained depend strongly on the diffuse or specular nature of the electron scattering a t the surface and also on the longitudinal or transverse orientation of the magnetic field relative to the current. The effect should be observable in degenerate semiconductors and semimetals a t infra-red frequencies.

THE EFFECT OF POSITION DEPENDENT EFFECTIVE MASS OF HYDROGENIC IMPURITIES IN PARABOLIC GaAs/GaAlAs QUANTUM DOTS IN A STRONG MAGNETIC FIELD

2009 ◽  
Vol 23 (26) ◽  
pp. 5109-5118 ◽  
Author(s):  
A. JOHN PETER
Keyword(s):  
Magnetic Field ◽  
Quantum Dots ◽  
Binding Energy ◽  
Effective Mass ◽  
Bound States ◽  
Mass Approximation ◽  
Infinite Case ◽  
Dependent Mass ◽  
The Magnetic Field ◽  
Peak Value

The binding energy of shallow hydrogenic impurities in parabolic GaAs/GaAlAs quantum dots is calculated as a function of dot radius in the influence of magnetic field. The binding energy has been calculated following a variational procedure within the effective-mass approximation. Calculations are presented with constant effective-mass and position dependent effective masses. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. The results show that the impurity binding energy (i) increases as the dot radius decreases for the infinite case, (ii) reaches a peak value around 1R* as the dot radius decreases and then diminishes to a limiting value corresponding to the radius for which there are no bound states in the well for the infinite case, and (iii) increases with the magnetic field. Also it is found that (i) the use of constant effective mass (0.067 m0) is justified for dot sizes ≥ a* where a* is the effective Bohr radius which is about 100 Å for GaAs , in the estimation of ionization energy and (ii) the binding energy shows complicated behavior when the position dependent mass is included for the dot size ≤ a*. These results are compared with the available existing literatures.

scholarly journals Ускорение электронов E-=SUB=-0n-=/SUB=--волной в круглом волноводе в режиме циклотронного резонанса

2020 ◽  
Vol 90 (6) ◽  
pp. 1022
Author(s):  
В.Н. Пашенцев ◽  
М.В. Пашенцева
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Cross Section ◽  
Cyclotron Resonance ◽  
State University ◽  
Spiral Trajectory ◽  
Synchronous Rotation ◽  
E Mail ◽  
Moscow State University ◽  
The Magnetic Field

Pashentsev V.N.1, Pashentseva M.V.2 1 National Research Nuclear University MEPhI 115409 Moscow, Russia 2 Lomonosov Moscow State University 119991 Moscow, Russia e-mail: [email protected] A method for accelerating electrons in a smooth cylindrical waveguide placed in the magnetic field of a solenoid is proposed. The motion of electrons in the waveguide occurs along a spiral trajectory shifted from the center of the waveguide. Electrons are accelerated at the cyclotron resonance frequency by the E01 or E02 waves in the direction of the waveguide axis. It is shown that the acceleration occurs as a result of synchronous rotation of particles in the cross section of the waveguide and the movement of the wave along the waveguide axis. When the electric field is maximum and has an decelerating direction, the electrons are in the center of the waveguide. Through the half-period, the direction of the electric field in the center will be braking, so under the influence of the magnetic field, the electrons rotate to the wall of the waveguide in the region of a smaller value of the decelerating electric field. It is shown that during the period of rotation of electrons the total effect of interaction of electrons with a wave is accelerating. The parameters of the accelerator for the energy of 10 MeV are estimated.

SEQUENTIAL RESONANT TUNNELING BETWEEN LANDAU LEVELS IN GaAs\AlGaAs SUPERLATTICES IN STRONG TILTED MAGNETIC AND ELECTRIC FIELDS

2007 ◽  
Vol 21 (08n09) ◽  
pp. 1594-1599 ◽  
Author(s):  
M. P. TELENKOV ◽  
YU. A. MITYAGIN
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electric Fields ◽  
Resonant Tunneling ◽  
Landau Levels ◽  
Domain Formation ◽  
Tunneling Transition ◽  
The Magnetic Field ◽  
Component Parallel ◽  
Tilted Magnetic Field

The transverse resonant tunneling transport and electric field domain formation in GaAs/AlGaAs superlattices were investigated in a strong tilted magnetic field. The magnetic field component parallel to structure layers causes intensive tunneling transition between Landau levels with Δn≠0, resulting in the considerable "inhomogeneous" broadening of intersubband tunneling resonance as well as in the shift of the resonance toward higher electric fields. This leads to noticeable changes of the I-V characteristics of the superlattice, namely to smoothing of the periodic NDC structure on plateau-like regions caused by formation of the electric field domains and to the shift of the plateaus toward the higher applied voltage. The predicted behavior of the I-V characteristics of the structures in magnetic field was found experimentally.

Erklärung stellarer und planetarer Magnetfelder durch einen turbulenzbedingten Dynamomechanismus

1966 ◽  
Vol 21 (8) ◽  
pp. 1285-1296 ◽  
Author(s):  
M. Steenbeck ◽  
F. Krause
Keyword(s):  
Magnetic Field ◽  
Angular Velocity ◽  
Magnetic Fields ◽  
Cross Product ◽  
Skin Depth ◽  
Electrically Conducting ◽  
Magnetic Stars ◽  
The Magnetic Field ◽  
Component Parallel ◽  
Good Agreement

In a foregoing paper 1 the effects of a turbulent motion on magnetic fields were investigated. Especially turbulence was treated under the influence of CORIOLiS-forces and gradients of density and/or turbulence intensity. It was shown that on these conditions the average cross-product of velocity and magnetic field has a non-vanishing component parallel to the average magnetic field. Here we give the consequences of this effect for rotating, electrically conducting spheres.At first a sphere rotating with constant angular velocity is investigated. The quadratic effect provides for dynamo maintainance of the magnetic fields. A field of dipol-type has the weakest condition for maintainance. Applications to the magnetic field of the earth show a good agreement with the conceptions of the physical state of the earth’s core.For a second model differential rotation is included. We have also dynamo maintainance. Since we have to assume that generally the angular velocity is a function decreasing with the distance from the centre of the sphere, the calculations show that we have a preferred self-excited build-up of a quadrupol-type field. This model may be applicable to magnetic stars.Finally we look for dynamo maintainance of alternating fields. We consider the skin-depth to be small compared with the radius of the sphere, then we have plane geometry. The existence of periodical solutions is proved. Applications to the general magnetic field of the sun, which has a period of 22 years, are discussed.

SHAPE EFFECT OF SEMIMAGNETIC QUANTUM DOT ON THE BOUND MAGNETIC POLARON

2011 ◽  
Vol 10 (04n05) ◽  
pp. 665-668 ◽  
Author(s):  
A. MERWYN JASPER DE REUBEN ◽  
K. JAYAKUMAR
Keyword(s):  
Magnetic Field ◽  
Variational Principle ◽  
Binding Energy ◽  
Quantum Dot ◽  
Effective Mass ◽  
Shape Effect ◽  
Magnetic Polaron ◽  
Bound Magnetic Polaron ◽  
Mass Approximation ◽  
The Magnetic Field

The effect of geometry, concentration of Mn ion and the magnetic field on the binding energy of a donor and the donor bound magnetic polaronic shift in a finite Cd 1–x1 Mn x1 Te / Cd 1–x2 Mn x2 Te Quantum Dot within the effective mass approximation is carried out employing the variational principle. The results are presented and discussed.

Sign in / Sign up

Export Citation Format

Share Document