POSSIBLE P-WAVE CONDENSED CONDUCTOR (OR SUPERCONDUCTOR) FOR La1-xCaxMnO3 FILMS

1999 ◽  
Vol 13 (29n31) ◽  
pp. 3799-3807
Author(s):  
Hyun-Tak Kim ◽  
Yong-Jihn Kim ◽  
Kwang-Yong Kang
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Two Dimensions ◽  
P Wave ◽  
Ferromagnetic Phase ◽  
Metal Insulator ◽  
Tunneling Conduction ◽  
Van Der Pauw ◽  
Two Phases ◽  
Electron Carriers

A ferromagnetic phase with electron carriers and a semiconducting phase with hole carriers were separated in La 1-x Ca x MnO 3 thin films by the van der Pauw method. We conclude that two phases are attributed to the metal-insulator instability. In the ferromagnetic phase for films with anisotropic moments in two dimensions, a remnant resistivity of the order of 10-8Ωm is observed up to 100 K and increases exponentially with temperature up to Tc and above one Tesla as a function of magnetic field strength (a positive magnetoresistivity). The phase below Tc is regarded as a polaronic state with a polaronic tunneling conduction. Possible p-wave condensation (or superconductor) with a parabolic density of states and the phase separation are discussed on the basis of the two-fold degeneracy of eg orbitals.

Magnetic-field-induced metal-insulator transition in two dimensions

1994 ◽  
Vol 72 (5) ◽  
pp. 709-712 ◽  
Author(s):  
T. Wang ◽  
K. P. Clark ◽  
G. F. Spencer ◽  
A. M. Mack ◽  
W. P. Kirk
Keyword(s):  
Magnetic Field ◽  
Two Dimensions ◽  
Insulator Transition ◽  
Metal Insulator Transition ◽  
Metal Insulator

Prediction of the Magneto-Resistance of La0.65Ca0.35MnO3 and La0.8Sr0.2MnO3 via Temperature and Magnetic Field

2013 ◽  
Vol 772 ◽  
pp. 83-88
Author(s):  
Ning Zhu ◽  
Ya Jie Liu
Keyword(s):  
Magnetic Field ◽  
Calculated Data ◽  
Ferromagnetic Phase ◽  
Metal Insulator ◽  
Nonlinear Fitting ◽  
Relative Errors ◽  
Magneto Resistance ◽  
Perovskite Type ◽  
The Magnetic Field ◽  
Crucial Parameter

The resistance associated with temperature and magnetic field is a crucial parameter in researching the physical properties of the Perovskite-type manganites. To find out a suitable method to predicting the resistance of La0.65Ca0.35MnO3and La0.8Sr0.2MnO3in the process from paramagnetic phase to the ferromagnetic phase via the temperature and the magnetic field was the aim of this paper. By the nonlinear fitting, an appreciated analytic expression showing the temperature-dependence resistance both less or higher than the metal-insulator transition temperature,Tc, at different magnetic field was put forward. All of the nonlinear fitting between the measured and the calculated data were so satisfied that the minimum correlation coefficient is below 0.9997, the average relative errors do not exceed 1.0%.

PERCOLATION APPROACH TO THE METAL–INSULATOR TRANSITION IN TWO DIMENSIONS

2001 ◽  
Vol 15 (19n20) ◽  
pp. 2641-2645
Author(s):  
YIGAL MEIR
Keyword(s):  
Magnetic Field ◽  
Critical Density ◽  
Metallic Phase ◽  
Two Dimensions ◽  
Insulator Transition ◽  
Exponential Dependence ◽  
Metal Insulator Transition ◽  
Electron Model ◽  
Metal Insulator ◽  
Model Combining

A simple non-interacting-electron model, combining local quantum tunneling via quantum point contacts and global classical percolation, is introduced in order to describe the observed "metal–insulator transition" in two dimensions.1 It is shown that many features of the experiments, such as the exponential dependence of the resistance on temperature on the metallic side, the linear dependence of the exponent on density, the e2/h scale of the critical resistance, the quenching of the metallic phase by a parallel magnetic field and the non-monotonic dependence of the critical density on a perpendicular magnetic field, can be naturally explained by the model.

Electrical Anisotropy of Thin Metal Films Growing on Dielectric Substrates

2002 ◽  
Vol 7 (2) ◽  
pp. 45-52
Author(s):  
L. Jakučionis ◽  
V. Kleiza
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Uniaxial Anisotropy ◽  
Metal Films ◽  
Thin Layers ◽  
Electrical Anisotropy ◽  
Electrical Field ◽  
Dielectric Substrates ◽  
Unequal Probability ◽  
Conductive Thin Films

Electrical properties of conductive thin films, that are produced by vacuum evaporation on the dielectric substrates, and which properties depend on their thickness, usually are anisotropic i.e. they have uniaxial anisotropy. If the condensate grow on dielectric substrates on which plane electrical field E is created the transverse voltage U⊥ appears on the boundary of the film in the direction perpendicular to E. Transverse voltage U⊥ depends on the angle γ between the applied magnetic field H and axis of light magnetisation. When electric field E is applied to continuous or grid layers, U⊥ and resistance R of layers are changed by changing γ. It means that value of U⊥ is the measure of anisotropy magnitude. Increasing voltage U0 , which is created by E, U⊥ increases to certain magnitude and later decreases. The anisotropy of continuous thin layers is excited by inequality of conductivity tensor components σ0 ≠ σ⊥. The reason of anisotropy is explained by the model which shows that properties of grain boundaries are defined by unequal probability of transient of charge carrier.

Magnetic Field Imaging on Stacked Flash Memories by Laser Probing and SQUID Scanning

2017 ◽  
Author(s):  
K. Sanchez ◽  
G. Bascoul ◽  
F. Infante ◽  
N. Courjault ◽  
T. Nakamura
Keyword(s):  
Magnetic Field ◽  
Failure Analysis ◽  
Two Dimensions ◽  
Analysis Tool ◽  
Active Device ◽  
Current Path ◽  
3D Packaging ◽  
Magnetic Field Imaging ◽  
The Magnetic Field ◽  
Field Imaging

Abstract Magnetic field imaging is a well-known technique which gives the possibility to study the internal activity of electronic components in a contactless and non-invasive way. Additional data processing can convert the magnetic field image into a current path and give the possibility to identify current flow anomalies in electronic devices. This technique can be applied at board level or device level and is particularly suitable for the failure analysis of complex packages (stacked device & 3D packaging). This approach can be combined with thermal imaging, X-ray observation and other failure analysis tool. This paper will present two different techniques which give the possibility to measure the magnetic field in two dimensions over an active device. Same device and same level of current is used for the two techniques to give the possibility to compare the performance.

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