| 1. |
|
|
| 2. |
- Kislinskiǐ, Yu V., et al.
(författare)
-
Magnetically Dependent Superconducting Transport in Oxide Heterostructures with an Antiferromagnetic Layer
- 2008
-
Ingår i: Journal of Experimental and Theoretical Physics. - 1090-6509 .- 1063-7761. ; 106:4, s. 800-805
-
Tidskriftsartikel (refereegranskat)abstract
- The superconducting current in hybrid superconducting structuresNb/Au/Ca1−xSrxCuO2/YBa2Cu3O7 –δwith an antiferromagnetic layer is experimentally shown to have aJosephson nature, and the deviation from the sinusoidal dependence of the superconducting current on thephase difference between superconducting electrodes is about 20% of the second harmonic. These heterostructuresare found to have sensitivity to an applied magnetic field that is much higher than that of conventionalJosephson junctions. The experimental shape of the magnetic-field dependence of the critical current in the heterostructuresdiffers from the usual Fraunhofer shape by oscillation with a significantly smaller period along amagnetic field.PACS numbers: 74.45.+c, 74.50.+r, 75.70.Cn
|
|
| 3. |
- Komissinskiy, Philipp, 1972, et al.
(författare)
-
High-frequency dynamics of hybrid oxide Josephson heterostructures
- 2008
-
Ingår i: Physical Review B - Condensed Matter and Materials Physics. - 2469-9950 .- 2469-9969. ; 78, s. 024501-15
-
Tidskriftsartikel (refereegranskat)abstract
- We summarize our results on Josephson heterostructures Nb/Au/YBa2Cu3Ox that combine conventional (S) and oxide high-Tc superconductors with a dominant d-wave symmetry of the superconducting order parameter(D). The heterostructures were fabricated on (001) and C1 1 20) YBa2Cu3Ox films grown by pulsed laser deposition. The structural and surface studies of the (1 1 20) YBa2Cu3Ox thin films reveal nanofaceted surface structure with two facet domain orientations, which are attributed as (001) and (110)-oriented surfaces of YBa2Cu3Ox and result in S/D(001) and S/D(110) nanojunctions formed on the facets. Electrophysical propertiesof the Nb/Au/YBa2Cu3Ox heterostructures are investigated by the electrical and magnetic measurements atlow temperatures and analyzed within the faceting scenario. The superconducting current-phase relation (CPR)of the heterostructures with finite first and second harmonics is derived from the Shapiro steps, which appearin the I-V curves of the heterostructures irradiated at frequencies up to 100 GHz. The experimental positionsand amplitudes of the Shapiro steps are explained within the modified resistive Josephson junction model,where the second harmonic of the CPR and capacitance of the Josephson junctions are taken into account. Weexperimentally observe a crossover from a lumped to a distributed Josephson junction limit for the size of theheterostructures smaller than Josephson penetration depth. The effect is attributed to the variations of theharmonics of the superconducting CPR across the heterojunction, which may give rise to splintered vortices of magnetic flux quantum. Our investigations of parameters and phenomena that are specific for superconductorshaving d-wave symmetry of the superconducting order parameter may be of importance for applications suchas high-frequency detectors and novel elements of a possible quantum computer.
|
|
| 4. |
|
|
| 5. |
- Ovsyannikov, Gennady, 1948, et al.
(författare)
-
Conductivity and antiferromagnetism of CaCuO2 thin films doped by Sr
- 2007
-
Ingår i: Physica C: Superconductivity and its Applications. - : Elsevier BV. - 0921-4534. ; 460-462:Part 1, 1 September 2007, s. 536-537
-
Tidskriftsartikel (refereegranskat)abstract
- The results of electrical and magnetic investigations of epitaxial CaxSr1-xCuO2 (CSCO) thin films grown by pulsed laser deposition are presented. The experimental temperature dependence of the CSCO film conductivity at low doping level is well described by the 3-d Mott insulator model over a wide temperature range (4.2-300 K). A deviation from the model with changing of Sr concentration has been observed. The Neel temperature of the films, T-N, was determined by electron paramagnetic resonance technique. The comparison of the obtained TN value with the one previously obtained for the CSCO powder sample could be caused by oxygen vacancies in the CSCO films. Nb/Au/Ca1-xSrxCuO2/YBa2Cu3O7-delta heterostructures have been fabricated and superconducting current has been observed at low temperatures. (c) 2007 Elsevier B.V. All rights reserved.
|
|
