Magnetic field, frequency and temperature dependence of complex conductance of ultrathin La1.65Sr0.45CuO4∕La2CuO4 films and the organic superconductors κ-(BEDT-TTF)2Cu[N(CN)2]Br

We used atomic-layer molecular beam epitaxy (ALL-MBE) to synthesize bilayer films of a cuprate metal ([Formula: see text], LSCO) and a cuprate insulator ([Formula: see text], LCO), in which interface superconductivity occurs in a layer that is just one-half unit cell thick. We have studied the magnetic field and temperature dependence of the complex sheet conductance, [Formula: see text], of these films, and compared them to [Formula: see text]-(BEDT-TTF)[Formula: see text] single crystals. The magnetic field [Formula: see text] was applied both parallel and perpendicular to the 2D conducting layers. Experiments have been carried out at frequencies between 23 kHz and 50 MHz using either two-coil mutual inductance technique, or the LC resonators with spiral or rectangular coils. The real and the imaginary parts of the mutual-inductance [Formula: see text] between the coil and the sample were measured and converted to complex conductivity. For [Formula: see text] perpendicular to the conducting layers, we observed almost identical behavior in both films and [Formula: see text]-Br single crystals: (i) the transition onset in the inductive response, [Formula: see text](T) occurs at a temperature lower by 2 K than in [Formula: see text], (ii) this shift is almost constant with magnetic field up to 8 T; (iii) the vortex diffusion constant [Formula: see text] is exponential due to pinning of vortex cores. These results can be described by the extended dynamic theory of the Berezinski–Kosterlitz–Thouless (BKT) transition and dynamics of bound vortex–antivortex pairs with short separation lengths.

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INFLUENCE OF LONGITUDINAL MAGNETIC FIELD ON THE FLUCTUATION CONDUCTIVITY IN SLIGHTLY Al-DOPED YBa2Cu3-zAlzO7-δ SINGLE CRYSTALS WITH A GIVEN TOPOLOGY OF PLANE DEFECTS

Modern Physics Letters B ◽

10.1142/s0217984911027327 ◽

2011 ◽

Vol 25 (27) ◽

pp. 2131-2136 ◽

Cited By ~ 41

Author(s):

R. V. VOVK ◽

M. A. OBOLENSKII ◽

A. A. ZAVGORODNIY ◽

Z. F. NAZYROV ◽

I. L. GOULATIS ◽

...

Keyword(s):

Magnetic Field ◽

Electrical Conductivity ◽

Theoretical Model ◽

Liquid Phase ◽

Temperature Dependence ◽

Single Crystals ◽

Constant Magnetic Field ◽

Longitudinal Magnetic Field ◽

Fluctuation Conductivity ◽

The Magnetic Field

In this work we study the influence of the constant magnetic field up to 14 kOe to the temperature dependence of the electrical conductivity in the ab-plane of aluminium doped YBa 2 Cu 3 O 7-δ single crystals with an unidirectional twin boundaries system. The temperature dependence of the excess para-conductivity is interpreted within the Aslamazov–Larkin theoretical model of the fluctuation conductivity. It was shown that the lack of fan-shaped expansion of the resistive transitions in the magnetic field in these samples may be due to the lack of the non-pinning vortex liquid phase.

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MATHEMATICAL MODELING OF TEMPERATURE EFFECT ON THE FAN CHART OF MAGNETOABSORPTION SPECTRUM IN SEMICONDUCTORS

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.01-03.104-115 ◽

2019 ◽

pp. 104-115

Author(s):

G. Gulyamov ◽

U. I. Erkaboev ◽

A. G. Gulyamov

Keyword(s):

Mathematical Modeling ◽

Magnetic Field ◽

Temperature Dependence ◽

Density Of States ◽

Landau Levels ◽

Joint Density ◽

Narrow Gap ◽

Narrow Gap Semiconductors ◽

Dispersion Law ◽

The Magnetic Field

The article considers the oscillations of interband magneto-optical absorption in semiconductors with the Kane dispersion law. We have compared the changes in oscillations of the joint density of states with respect to the photon energy for different Landau levels in parabolic and non-parabolic zones. An analytical expression is obtained for the oscillation of the combined density of states in narrow-gap semiconductors. We have calculated the dependence of the maximum photon energy on the magnetic field at different temperatures. A theoretical study of the band structure showed that the magnetoabsorption oscillations decrease with an increase in temperature, and the photon energies nonlinearly depend on a strong magnetic field. The article proposes a simple method for calculating the oscillation of joint density of states in a quantizing magnetic field with the non-quadratic dispersion law. The temperature dependence of the oscillations joint density of states in semiconductors with non-parabolic dispersion law is obtained. Moreover, the article studies the temperature dependence of the band gap in a strong magnetic field with the non-quadratic dispersion law. The method is applied to the research of the magnetic absorption in narrow-gap semiconductors with nonparabolic dispersion law. It is shown that as the temperature increases, Landau levels are washed away due to thermal broadening and density of states turns into a density of states without a magnetic field. Using the mathematical model, the temperature dependence of the density distribution of energy states in strong magnetic fields is considered. It is shown that the continuous spectrum of the density of states, measured at the temperature of liquid nitrogen, at low temperatures turns into discrete Landau levels. Mathematical modeling of processes using experimental values of the continuous spectrum of the density of states makes it possible to calculate discrete Landau levels. We have created the three-dimensional fan chart of magneto optical oscillations of semiconductors with considering for the joint density of energy states. For a nonquadratic dispersion law, the maximum frequency of the absorbed light and the width of the forbidden band are shown to depend nonlinearly on the magnetic field. Modeling the temperature dependence allowed us to determine the Landau levels in semiconductors in a wide temperature spectrum. Using the proposed model, the experimental results obtained for narrow-gap semiconductors are analyzed. The theoretical results are compared with experimental results.

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Temperature dependence of the magnetic-field-induced strain of NiMnGa in the presence of an acoustic drive

Journal of Applied Physics ◽

10.1063/1.2824895 ◽

2008 ◽

Vol 104 (3) ◽

pp. 033918 ◽

Cited By ~ 9

Author(s):

Bradley W. Peterson ◽

Samuel M. Allen ◽

Robert C. O’Handley

Keyword(s):

Magnetic Field ◽

Temperature Dependence ◽

The Magnetic Field

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Orientation dependence of the magnetic field distributions in large single crystals of

Physica B Condensed Matter ◽

10.1016/j.physb.2005.11.061 ◽

2006 ◽

Vol 374-375 ◽

pp. 225-228 ◽

Cited By ~ 1

Author(s):

W.J. Kossler ◽

A.J. Greer ◽

R.N. Dickes ◽

D. Sicilia ◽

Y. Dai

Keyword(s):

Magnetic Field ◽

Single Crystals ◽

Orientation Dependence ◽

Field Distributions ◽

The Magnetic Field

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On the magnetic field dependence of critical current density in single crystals of high-Tc superconductors

Physica C Superconductivity ◽

10.1016/0921-4534(94)90487-1 ◽

1994 ◽

Vol 226 (1-2) ◽

pp. 133-142 ◽

Cited By ~ 15

Author(s):

K. Yamafuji ◽

T. Fujiyoshi ◽

K. Toko ◽

T. Matsuno ◽

T. Kobayashi ◽

...

Keyword(s):

Magnetic Field ◽

Critical Current Density ◽

Single Crystals ◽

Critical Current ◽

Field Dependence ◽

Current Density ◽

Magnetic Field Dependence ◽

High Tc Superconductors ◽

High Tc ◽

The Magnetic Field

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Crystal Perfection of Silicon Single Crystals Grown by the Magnetic‐Field‐Applied Czochralski Method

Journal of The Electrochemical Society ◽

10.1149/1.2108515 ◽

1986 ◽

Vol 133 (1) ◽

pp. 171-174 ◽

Cited By ~ 5

Author(s):

Seiji Kawado ◽

Toshiyuki Maruyama ◽

Toshihiko Suzuki ◽

Nobuyuki Isawa ◽

Kinji Hoshi

Keyword(s):

Magnetic Field ◽

Single Crystals ◽

Czochralski Method ◽

Crystal Perfection ◽

The Magnetic Field

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Effects of Vortex Pinning on the Temperature Dependence of the Magnetic Field Distributions in Superconductors

Physics Procedia ◽

10.1016/j.phpro.2012.04.083 ◽

2012 ◽

Vol 30 ◽

pp. 245-248

Author(s):

W.J. Kossler ◽

Allan J. Greer ◽

Dale R. Harshman ◽

C.E. Stronach ◽

A.C. Shockley ◽

...

Keyword(s):

Magnetic Field ◽

Temperature Dependence ◽

Vortex Pinning ◽

Field Distributions ◽

The Magnetic Field

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Magnetic Prehistory in the Heat Capacity of the Low-Temperature Superconductors

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.741 ◽

2015 ◽

Vol 233-234 ◽

pp. 741-744

Author(s):

Sergey Mikhailovich Podgornykh

Keyword(s):

Magnetic Field ◽

Heat Capacity ◽

External Magnetic Field ◽

Low Temperature ◽

Temperature Dependence ◽

Zero Magnetic Field ◽

Zero Field ◽

Ring Specimen ◽

Trapped Flux ◽

The Magnetic Field

Effect of the magnetic prehistory on the temperature dependence of the heat capacity of the superconducting Pb, La, Sn. has been studied. As soon as the external magnetic field riches the valueHext=HCthe superconductivity is completely destroyed. The trapped flux was produced in the ring specimen after the magnetic field was turned off atT<TC. We observed a difference of the value of the heat capacity between zero field cooled (ZFC) and field cooled (FC) states in zero magnetic field for the ring specimen. It is found that the FC heat capacity is smaller than the heat capacity both in the normal and in superconducting states.

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