Temperature dependence of the low field microwave loss in hafnium doped YBaCuO superconductor

Epitaxial CrO 2 (100)-oriented film was successfully fabricated on TiO 2 (100) substrate by a simple chemical vapor deposition in a two-zone furnace with oxygen flow from a CrO 3 precursor. The transport measurements show that the CrO 2 film is metallic with a small residual resistivity 4 μΩ cm down to 0.6 K. The temperature dependence of resistivity was best described by a phenomenological expression ρ(T) = ρ0 + AT2 exp (-Δ/T) over the range of 0.6–300 K with Δ = 123.6 K. The magnetization of the film becomes saturated in a relatively low field with a small coercive field. The temperature dependence of magnetization shows Bloch's T3/2 law and the slope of the curve suggests a critical wavelength of λΔ ~ 26.6 Å beyond which spin-flip scattering becomes important.

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Determination of Density of Localized States in Amorphous Silicon Alloys From the Low Field Conductance of Thin N-I-N Diodes

MRS Proceedings ◽

10.1557/proc-49-69 ◽

1985 ◽

Vol 49 ◽

Cited By ~ 7

Author(s):

Michael Shur ◽

Michael Hack

Keyword(s):

Temperature Dependence ◽

Amorphous Silicon ◽

Bulk Density ◽

Density Of States ◽

Energy Gap ◽

Localized States ◽

New Technique ◽

Silicon Alloys ◽

Low Field ◽

Density Of Localized States

AbstractWe describe a new technique to determine the bulk density of localized states in the energy gap of amorphous silicon alloys from the temperature dependence of the low field conductance of n-i-n diodes. This new technique allows us to determine the bulk density of states in the centre of a device, and is very straightforward, involving fewer assumptions than other established techniques. Varying the intrinsic layer thickness allows us to measure the,density of states within approximately 400 meV of midgap.We measured the temperature dependence of the low field conductance of an amorphous silicon alloy n-i-n diode with an intrinsic layer thjckness of 0.45 microns and deduced the density of localised states to be 3xlO16cm−3 eV−1 at approximately 0.5 eV below the bottom of the conduction band. We have also considered the high bias region (the space charge limited current regime) and proposed an interpolation formula which describes the current-voltage characteristics of these structures at all biases and agrees well with our computer simulation based on the solution of the complete system of transport equations.

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Temperature dependence of low field switching and coercive field in ferroelectric TGS

Ferroelectrics Letters Section ◽

10.1080/07315179908204579 ◽

1999 ◽

Vol 25 (1-2) ◽

pp. 17-25 ◽

Cited By ~ 2

Author(s):

C. Aragó ◽

B. Noheda ◽

J. R. Fdez Del Castillo ◽

J. A. Gonzalo ◽

S. Mielcarek

Keyword(s):

Temperature Dependence ◽

Coercive Field ◽

Low Field

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Temperature dependence of the low field microwave absorption of high Tc superconductors

Physics Letters A ◽

10.1016/0375-9601(88)90457-4 ◽

1988 ◽

Vol 133 (6) ◽

pp. 339-341 ◽

Cited By ~ 7

Author(s):

A.R. Harutyunyan ◽

L.S. Grigoryan ◽

M. Baran ◽

S. Piechota

Keyword(s):

Temperature Dependence ◽

Microwave Absorption ◽

High Tc Superconductors ◽

High Tc ◽

Low Field

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ESR STUDIES OF GMR RELATED MATERIALS I: ESR of Mn IN LaMnO3 AND La0.99Ca0.01MnO3

Modern Physics Letters B ◽

10.1142/s0217984900001191 ◽

2000 ◽

Vol 14 (25n26) ◽

pp. 883-897 ◽

Cited By ~ 3

Author(s):

N. ARAI ◽

K. SUGAWARA

Keyword(s):

Magnetic Susceptibility ◽

Temperature Dependence ◽

Spin System ◽

High Field ◽

Energy Gap ◽

Low Field ◽

High Field Esr ◽

Clear Signal ◽

Spin Clusters ◽

G Value

ESR measurements are carried out for La 1-x Ca x MnO 3 (x=0, 0.01) from 760 K down to 4 K. A clear signal was observed above 260 K, presumably arising from Mn 3+ and Mn 4+, but two kinds of signals, the low-field and high-field ESR with g≃2, were observed below it. The high- and low-field signals are tentatively assumed to originate from Mn 4+ and Mn 3+, respectively. The g-value, linewidth, and intensity of the high-field signal nearly follow ∝1/(T-106). The temperature dependence of g-shift of the low-field signal is similar to that of magnetic susceptibility of LaMnO 3. The ESR intensity anomalously increases at temperatures between about 150 K and 250 K, which is tentatively ascribed to the occurrence of "spin-clusters". Above ≃300 K, the ESR intensity nearly follows Curie's law, and the linewidth is proportional to exp (-500/T), an indication of some kind of energy-gap existence in the Mn spin system.

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