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1.
Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
2.
Horst Luckhardt 《Archive for Mathematical Logic》1970,13(1-2):55-59
Ohne Zusammenfassung 相似文献
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4.
Horst Luckhardt 《manuscripta mathematica》1969,1(3):241-257
For simple type theory with -conversion, extensionality and classical, intuitionistic or minimal predicate logic together with M-, Br-, S4- or S5-modalities as examples it is shown that it is possible to obtain Skolemnormalforms only by applying transpositions, i.e. replacements of equivalent subformulae. In this way one gets in classical type theory without modalities a provable equivalent normalform with prefix and with S5-modalities a deductive equivalent prenex normalform of the form. The axiom of choice allows further simplifications: for example in classical simple type theory a provable equivalent normalform with prefix. 相似文献
5.
Horst Von Luckhardt 《Archive for Mathematical Logic》1977,18(1):73-80
Ohne ZusammenfassungIn einer Fortsetzung dieser (im Mai 1974 abgeschlossenen) Arbeit wird die Untersuchung unter Berücksichtigung der inzwischen erschienenen Literatur weitergeführt. 相似文献
6.
CoFe2O4-BaTiO3 composites were prepared using conventional ceramic double sintering process with various compositions. Presence of two phases
in the composites was confirmed using X-ray diffraction. The dc resistivity and thermoemf as a function of temperature in
the temperature range 300 K to 600 K were measured. Variation of dielectric constant (ɛ′) with frequency in the range 100 Hz to 1 MHz and also with temperature at a fixed frequency of 1 kHz was studied. The ac
conductivity was derived from dielectric constant (ɛ′) and loss tangent (tan δ). The nature of conduction is discussed on the basis of small polaron hopping model. The static value of magnetoelectric
conversion factor has been studied as a function of magnetic field. 相似文献
7.
A Gurtu P K Malhotra I S Mittra P M Sood SC Gupta VK Gupta GL Kaul LK Mangotra Y Prakash NK Rao ML Sharma 《Pramana》1974,3(5):311-322
This is a continuation of our earlier investigation (Gurtuet al 1974Phys. Lett. 50 B 391) on multiparticle production in proton-nucleus collisions based on an exposure of emulsion stack to 200 GeV/c beam at the NAL. It is found that the ratioR em = 〈n s〉/〈n ch〉, where 〈n ch〉 is the charged particle multiplicity in pp-collisions, increases slowly from about 1 at 10 GeV/c to 1·6 at 68 GeV/c and attains a constant value of 1·71 ± 0·04 in the region 200 to 8000 GeV/c. Furthermore,R em = 1·71 implies an effectiveA-dependence ofR A =A 0.18,i.e., a very weak dependence. Predictions ofR em on various models are discussed and compared with the emulsion data. Data seem to favour models of hadron-nucleon collisions in which production of particles takes place through adouble step mechanism,e.g., diffractive excitation, hydrodynamical and energy flux cascade as opposed to models which envisage instantaneous production. 相似文献
8.
Horst Luckhardt 《Archive for Mathematical Logic》1968,10(1-2):37-58
Ohne ZusammenfassungDies ist der erste Teil einer Arbeit, die von der Naturwissenschaftlichen Fakultät der Phillips-Universität Marburg/Lahn als Dissertation angenommen wurde.Der Verfasser dankt seinem verehrten Lehrer, Herrn Professor H. Arnold Schmidt, der ihm in seinen Vorlesungen, seinen Seminaren und zahlreichen Gesprächen einen tiefen Kontakt zur Mathematik, insbesondere zur mathematischen Grundlagenforschung, vermittelt hat. 相似文献
9.
H. Luckhardt 《Mathematical Logic Quarterly》1979,25(30):475-479
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