| 1. |
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| 2. |
- MAGNUSSON, J, et al.
(författare)
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FLUX PINNING IN YBA2CU3O7 THIN-FILMS GROWN BY DC MAGNETRON SPUTTERING
- 1992
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Ingår i: Cryogenics (Guildford). - : Elsevier BV. - 0011-2275 .- 1879-2235. ; 32, s. 1084-1088
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Tidskriftsartikel (refereegranskat)abstract
- Thin films of YBa2Cu3O7 (YBCO) were deposited on single crystalline LaAlO3 substrates using d.c. magnetron sputtering. The quality of the films has been assessed by X-ray diffraction; YBa2Cu3O7 grows epitaxially with the c-axis parallel to the substrate normal. For some choices of the deposition parameters in the sputtering process, it was found that secondary phases were precipitated in the films. By a deliberate choice of deposition parameters, semi-coherently grown Y2O3 (yttria) inclusions could be obtained. They had square platelet or cubical shapes with sizes from 5 - 20 nm and thickness approximately 10 nm. The superconducting properties of the YBa2Cu3O7 films were investigated using SQUID magnetometry. Magnetization measurements on films with different densities of semicoherent Y2O3 inclusions indicate an enhanced flux pinning capability with increasing inclusion density.
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| 3. |
- NISKANEN, K, et al.
(författare)
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ANGULAR DEPENDENT MAGNETIC-PROPERTIES OF SINGLE-CRYSTAL BI-SR-CA-CU-O
- 1991
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Ingår i: Physica. C, Superconductivity. - 0921-4534 .- 1873-2143. ; 185, s. 2207-2208
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Tidskriftsartikel (refereegranskat)abstract
- The field, time and temperature dependence of the longitudinal component of the magnetization of a single crystal of BiSrCaCuO has been investigated by SQUID-magnetometry as a function of the tilt angle between the crystallographic c-axis and the applied magnetic field. We here discuss the results on the field and angular dependence of the magnetic response in zero field cooled magnetization experiments at low fields.
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| 4. |
- NISKANEN, K, et al.
(författare)
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ANISOTROPY IN SINGLE CRYSTALLINE BISRCACUO
- 1992
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Ingår i: Superconductors Science and Technology. - 0953-2048 .- 1361-6668. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- The longitudinal component of the magnetization of a single crystal of Bi2.2Sr1.7CaCu2O8 has been investigated by SQUID-magnetometry when the magnetic field is applied at different angles 0-degrees-90-degrees with respect to the crystallographic c-axis. The anisotropy of the system, deduced from the magnetization and relaxation rate data, indicates a mass anisotropy m(c)/m(ab) of order 20, a strikingly low value compared to what has been found from torque and magnetoresistance measurements m(c)/m(ab) almost-equal-to 3000.
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| 5. |
- NISKANEN, K, et al.
(författare)
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NONLOGARITHMIC MAGNETIC-RELAXATION IN BI-SR-CA-CU-O SINGLE-CRYSTALS
- 1991
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Ingår i: Superconductors Science and Technology. - 0953-2048 .- 1361-6668. ; 4
-
Tidskriftsartikel (refereegranskat)abstract
- The time dependence of the low field susceptibility of a Bi2.2Sr1.7CaCu2O8 single crystal has been investigated in the field range 0.1-300 gauss and at temperatures 0.25 less-than-or-equal-to T/T(c) less-than-or-equal-to 0.9. The relaxation of the magnetization is found to change from a logarithmic to a non-logarithmic form as the applied field is increased, implying that a conventional flux creep model cannot sufficiently describe the behaviour.
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| 6. |
- NORLING, P, et al.
(författare)
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MAGNETIC-RELAXATION OF INTERGRANULAR CRITICAL-STATE IN SINTERED YBA2CU3O7-DELTA
- 1994
-
Ingår i: Physica. C, Superconductivity. - : Elsevier BV. - 0921-4534 .- 1873-2143. ; 221, s. 169-176
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Tidskriftsartikel (refereegranskat)abstract
- The relaxation of the zero-field-cooled magnetisation of three sintered samples of YBa2Cu3O7-delta has been measured at low fields. Special attention was paid to the low-field regime where the motion of intergranular vortices is dominating the decay of the magnetisation. From the measured data the apparent activation energy for flux jumps, U0, was calculated. The extracted values fall in the range 0.6-2 eV, considerably higher than what has been found for the intragranular flux creep but in the same range as reported by others for intergranular creep. The samples showed somewhat different behaviours and the sample with the most homogeneous morphology had the lowest value of U0. This can be explained within theories for pinning in granular superconductors.
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| 7. |
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| 8. |
- SVEDLINDH, P, et al.
(författare)
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MAGNETIC-RELAXATION IN AN ISOTROPIC EXTREME TYPE-II SUPERCONDUCTOR
- 1991
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 43, s. 2735-2741
-
Tidskriftsartikel (refereegranskat)abstract
- The time dependence of the zero-field-cooled and thermoremanent magnetization of the isotropic extreme type-II superconductor PbMo6S8 has been measured at temperatures 0.7 less-than-or-equal-to T/T(c) less-than-or-equal-to 0.95 and for fields 1 less-than-or-equal-to H less-than-or-equal-to 300 G. The results show that the time dependence of the decay can be divided into three different field regimes: (1) A low-field regime with a closely logarithmic decay and a well-established critical state. The relaxation rate [partial M/partial ln(t)] increases as H-5 for the zero-field-cooled magnetization and as H-2.4 for the thermoremanent magnetization. The reduction in magnetization over 5 decades in time (0.3-3 X 10(4) s) is, at most, a few percent. (2) A crossover-field regime with a change from a logarithmic to a nonlogarithmic decay. (3) A high-field regime where the time dependence of the decay is well described by the expression delta-M approximately [ln(t/tau-0)]-alpha. The reduction in magnetization in the crossover- and high-field regimes is as large as 25-30% in the measured time interval. The results in the high-field regime are interpreted within the theory of collective flux creep. Comparisons are made with the magnetic relaxation found in anisotropic high-T(c) superconductors.
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| 9. |
- SVEDLINDH, P, et al.
(författare)
-
NONLOGARITHMIC MAGNETIC-RELAXATION IN BI2.2SR1.7CACU2O8 SINGLE-CRYSTALS - EVIDENCE FOR COLLECTIVE FLUX PINNING
- 1991
-
Ingår i: Physica. C, Superconductivity. - 0921-4534 .- 1873-2143. ; 176, s. 336-346
-
Tidskriftsartikel (refereegranskat)abstract
- High precision magnetic relaxation measurements have been performed on BiSrCaCuO single crystals with the field H applied parallel to the c-axis. At temperatures T/T(c) > 0.5, the data exhibit two different field regimes. One for H < H* (H* corresponds to the field where full flux penetration of the sample is achieved) where the ZFC and RM magnetization relaxes logarithmically with time in agreement with the conventional flux creep model; a second one for H > H* where the relaxation follows a [ln(t/t0)]-alpha dependence. This relaxation law is predicted in the collective flux creep theory for J << J(c) as well as in the vortex-glass model. In the temperature range 0.25 < T/T(c) < 0.4, there is a change in character of the measured decay of the magnetization. This change in character is interpreted to arise from thermal fluctuations of the flux-line lattice giving rise to a considerable reduction in the pinning strength above the depinning temperature.
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| 10. |
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| 11. |
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| 12. |
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| 13. |
- Ginnarsson, K., et al.
(författare)
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Equilibrium and nonequilibrium magnetic behaviour of a reentrant Ising spin glass.
- 1992
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Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 104-107:3, s. 1607-1608
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Tidskriftsartikel (refereegranskat)abstract
- The reentrant Ising spin glass Fe0.62Mn0.38TiO3 has been investigated using SQUID magnetometry. The system is antiferromagnetic below TN(H = 0) = 33 K, and enters a mixed antiferromagnetic/spin glass phase below Tg(H = 0) = 25.8 K. Within the concept of a recent mean field model, a ratio TN(0)/Tg(0) close to unity indicates both intra- and interlayer frustration. The existence of an overlap length, lΔT, below which equilibrium spin correlations at temperatures T and T + ΔT are indistinguishable has been verified by magnetic relaxation experiments on this spin glass system
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| 14. |
- GRANBERG, P, et al.
(författare)
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DYNAMICS OF COUPLED 2-DIMENSIONAL CU(MN) SPIN-GLASS FILMS
- 1991
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 44, s. 4410-4414
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Tidskriftsartikel (refereegranskat)abstract
- Time-dependent susceptibility measurements have been performed on multilayered two-dimensional (2D) 40-angstrom-wide Cu0.865Mn0.135 spin-glass films, separated by Cu interlayers of width 10 < w(il) < 1200 angstrom. It is found that samples with w(il) < 30 angstrom display 3D dynamic behavior. For 30 < w(il) < 600 angstrom a gradual decoupling of the spin-glass layers occurs, and for w(il) greater-than-or-equal-to 600 angstrom typical 2D behavior is observed. The effect of a finite interlayer coupling on the dynamic susceptibility is a distinct crossover from 2D dynamic behavior at short observation times to 3D dynamic behavior at long times. A clear influence on the spin-glass dynamics is still observable for interlayer thicknesses of order 500 angstrom; i.e., multilayered spin-glass films are extremely sensitive probes of the effective range of Ruderman-Kittel-Kasuya-Yosida interaction mediated via metallic interlayers. The results also yield information on the relation between time scale and length scale in relaxation experiments, a fundamental concept of domain theories of the spin-glass phase.
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| 15. |
- GRANBERG, P, et al.
(författare)
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NONEQUILIBRIUM RELAXATION IN A CU(MN) SPIN-GLASS
- 1990
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 92, s. 228-232
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Tidskriftsartikel (refereegranskat)abstract
- The zero-field dynamics of a Cu(10 at% Mn) spin glass system has been investigated by means of zero-field-cooled magnetization measurements. By subjecting the sample to specific temperature variations just before the field application, new information about the nature of the spin glass phase is obtained. The results are in accord with some predictions from domain theories on the behaviour of the magnetic relaxation in spin glasses. Specifically, the experimental results support the prediction that the spin glass dynamics is governed by an interplay between a growing domain size and the overlap length.
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| 16. |
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| 17. |
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| 18. |
- GUNNARSSON, K, et al.
(författare)
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STATIC SCALING IN A SHORT-RANGE ISING SPIN-GLASS
- 1991
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 43, s. 8199-8203
-
Tidskriftsartikel (refereegranskat)abstract
- The nonlinear ac susceptibility chi’-nl of the short-range Ising spin glass Fe0.5Mn0.5TiO3 has been measured using a superconducting-quantum-interference-device magnetometer. The spin-glass temperature, T(g), and the critical exponent gamma were estimated from the temperature dependence of the quadratic field term of chi’nl, yielding T(g) = 20.70 and gamma = 4.0. Static-scaling analyses, using different scaling equations, gave similar results. Using gamma and results from previous dynamic-scaling analyses, a number of critical exponents have been obtained through different scaling relations, e.g., delta = 8.4 and nu = 1.7. The results support the existence of a finite-temperature phase transition in a three-dimensional Ising spin glass.
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| 19. |
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| 20. |
- MATTSSON, J, et al.
(författare)
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AGING IN A 2-DIMENSIONAL CUMN SPIN-GLASS
- 1992
-
Ingår i: Journal of Magnetism and Magnetic Materials. - 0304-8853 .- 1873-4766. ; 104, s. 1623-1624
-
Tidskriftsartikel (refereegranskat)abstract
- Utilizing zero-field cooled magnetization measurements the nonequilibrium dynamics in a 2D spin glass film is investigated. The experiments show that aging is an inherent property of 2D spin glass systems with qualitatively similar features as in 3D systems.
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| 21. |
- MATTSSON, J, et al.
(författare)
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MULTILAYERED SPIN-GLASS FILMS - SENSITIVE PROBES OF RKKY
- 1992
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 104, s. 1619-1620
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Tidskriftsartikel (refereegranskat)abstract
- A new method that uses superstructures of Cu(Mn) spin glass films separated by metallic interlayers to probe the decay with thickness of the RKKY interaction within the interlayers is discussed.
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| 22. |
- MATTSSON, J, et al.
(författare)
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NONLINEAR SUSCEPTIBILITY OF 2D SPIN-GLASS FILMS
- 1992
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 104, s. 1621-1622
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Tidskriftsartikel (refereegranskat)abstract
- A careful study of the nonlinear susceptibility of multilayered two-dimensional Cu(14 at% Mn) spin glass layers separated by thick interlayers of Cu is reported. The experiments were performed in SQUID magnetometers using an ac susceptibility technique in the field range 0-0.5 kG and dc magnetization measurements in the field range 0-10 kG. The static 2D critical exponents have been determined from scaling analyses.
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| 23. |
- NISKANEN, K, et al.
(författare)
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ANTI-MEISSNER EFFECT AND LOW-FIELD MAGNETIC-RELAXATION IN SINTERED BI-2212
- 1994
-
Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 194, s. 1549-1550
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Tidskriftsartikel (refereegranskat)abstract
- A detailed study of the low field magnetic properties of some sintered Bi-2212 samples has been performed. For sufficiently low applied magnetic fields, typically for fields H < 0.2 Oe, the field-cooled magnetisation becomes positive at some temperature below T(C) (anti-Meissner effect), contrary to the usual Meissner effect. The field dependence of this effect is comparable to the predicted behaviour for a system in an orbital glass state. Additionally, the relaxation of the zero-field-cooled magnetisation displays an unexpected field dependence, the relaxation rate S = partial-derivative M/partial-derivative log(t) increases as H(alpha) with alpha almost-equal-to 0.9 at very low fields. In contrast to the behaviour found in sintered YBCO, this result is not accounted for in conventional flux creep models, where the prediction is alpha greater-than-or-equal-to 2.
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| 24. |
- ANDERSSON, JO, et al.
(författare)
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OVERLAP LENGTH IN A CU-MN SPIN-GLASS PROBED BY AC SUSCEPTIBILITY
- 1993
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 48, s. 13977-13980
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Tidskriftsartikel (refereegranskat)abstract
- An important theoretical concept in the ‘’droplet” model of spin glasses is the existence of an overlap length. Experimentally this concept was verified by dc-magnetization measurements. However, recent ac-susceptibility measurements by Lefloch et al. [Europhys. Lett. 18, 647 (1992)] have been interpreted to contradict this result. In this paper, ac-susceptibility and dc-magnetization measurements on a Cu (2% Mn) spin glass are reported. The results of the ac-susceptibility measurements are consistent with dc measurements and provide evidence for the existence of an overlap length in 3d spin glasses at low temperatures.
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| 25. |
- BAJOREK, A, et al.
(författare)
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ON EXCHANGE MECHANISM IN HG1-XMNXS
- 1994
-
Ingår i: Journal of Magnetism and Magnetic Materials. - 0304-8853 .- 1873-4766. ; 131, s. 363-368
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic susceptibility of Hg0.95Mn0.05S and Hg0.90Mn0.10S was measured by the SQUID technique. The experimental data were compared with the extended nearest neighbour pair approximation (ENNPA) calculation. The long range exchange interaction J = J(NN)R(-n), with the exponent n = 4, was found for both samples. The nearest neighbour exchange integral J(NN) was found to be around two times smaller than the effective exchange integral J(eff). The small value of the exponent n, which is a characteristic of the narrow gap semimagnetic semiconductors (SMSC’s), as well as the small J(NN)/J(eff) ratio, show the importance of a long-range exchange mechanism.
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| 26. |
- DJURBERG, C, et al.
(författare)
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RELAXATION OF THE FIELD COOLED MAGNETIZATION IN 2D CU(MN) FILMS
- 1994
-
Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 194, s. 303-304
-
Tidskriftsartikel (refereegranskat)abstract
- The relaxation of the field cooled magnetisation of a multilayered 2D Cu(Mn) spin glass film has been investigated in a SQUID-magnetometer. The sample is cooled in a constant magnetic field (10 Oe) from a high temperature, where the magnetisation is at equilibrium, to a temperature below the freezing temperature, T(f). At constant temperature, the magnetisation is then found to increase with time at temperatures near T(f), showing an initial decrease followed by an increase at long time scales at intermediate temperatures and only decreases with time at lower temperatures. The behaviour, including the surprising downward relaxation away from the thermodynamic equilibrium magnetisation, is qualitatively interpreted in terms of a spin glass domain model.
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| 27. |
- DJURBERG, C, et al.
(författare)
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REMANENT MAGNETIZATION IN THE DILUTED ISING ANTIFERROMAGNET FE0.6ZN0.4F2
- 1994
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 75, s. 5541-5543
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Tidskriftsartikel (refereegranskat)abstract
- The field, H less-than-or-equal-to 5 T, and temperature, T greater-than-or-equal-to 2 K, dependence of the remanent magnetization mu of the diluted Ising antiferromagnet Fe0.6Zn0.4F2 has been investigated utilizing a superconducting quantum interference device magnetometer. The results at low temperatures, where there is no growth of random field domains after the field removal, are analyzed according to mu = AH(x)(T ln t/t0)-PSI + B, where the two terms are domain wall and volume contributions to the remanent magnetization, respectively. It is found that PSI decreases continuously with decreasing temperature, and reaches a value of almost-equal-to 0.15 at 3 K. The field exponent x is found to decrease with increasing temperature, attaining values between 2 and 3. The results show a more complex behavior of the low-temperature remanent magnetization than a model proposed by Nattermann and Vilfan which predicts constant values of the exponents: PSI almost-equal-to 0.4 and x almost-equal-to 2.
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| 28. |
- HUDNER, J, et al.
(författare)
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PREPARATION OF YBA2CU3O7-X FILMS AND YBA2CU3O7-X/Y2O3 MULTILAYERS USING COEVAPORATION AND ATOMIC OXYGEN
- 1993
-
Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 73, s. 3096-3098
-
Tidskriftsartikel (refereegranskat)abstract
- Thin layers of YBa2Cu3O7-x (YBCO) deposited on LaAlO3 substrates have been prepared in situ by coevaporation of Y, Ba, and Cu. Incorporation of oxygen was accomplished by an atomic oxygen beam source with high cracking efficiency. The total oxygen flow at the substrate could be kept low enough to permit the use of a quadrupole mass spectrometer for evaporation rate monitoring. Films were strongly c-axis oriented with rocking curve full width at half-maximum values of 0.6-degrees. Transport measurements on patterned films yielded critical current densities of 6 x 10(6) A/cm2 at 77 K. The deposition method was demonstrated to be feasible for preparation of Y2O3/YBCO heterostructures.
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| 29. |
- KUSHAUER, J, et al.
(författare)
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CROSSOVER FROM LOGARITHMICALLY RELAXING TO PIEZOMAGNETICALLY FROZEN MAGNETIC REMANENCE IN LOW-FIELD-COOLED FE0.47ZN0.53F2
- 1994
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 49, s. 6346-6349
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Tidskriftsartikel (refereegranskat)abstract
- Weak-field-induced magnetization M and temporal relaxation of its remanence mu are investigated in Fe0.47Zn0.53F2 by using Faraday rotation and superconducting quantum interference device (SQUID) magnetometry. Stretched logarithmic decay as predicted by Nattermann and Vilfan is confirmed at T = 2.8 K for freezing fields 3 less-than-or-equal-to B less-than-or-equal-to 4.9 T. At very low fields, 0.001 less-than-or-equal-to B less-than-or-equal-to 1.5 T, virtually constant remanence, mu approximately 44 A/m, is observed. It is due to immobile domains, which form via piezomagnetic coupling to built-in random stress fields.
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| 30. |
- MATTSSON, J, et al.
(författare)
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DETERMINATION OF THE CRITICAL EXPONENT-BETA FROM MEASUREMENTS OF A WEAK SPONTANEOUS MAGNETIZATION IN THE 3D ISING ANTIFERROMAGNET FEF2
- 1994
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 136
-
Tidskriftsartikel (refereegranskat)abstract
- The critical exponent for the order parameter, beta, has been determined from the temperature dependence of a weak spontaneous magnetisation that appears below the Neel temperature in the prototypical 3d Ising antiferromagnet FeF2. The derived value of beta = 0.325 +/- 0.002 agrees with the theoretically calculated value for beta of a 3d Ising system. The very occurrence of a spontaneous magnetisation in pure FeF2 is assumed to be of piezomagnetic origin.
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| 31. |
- MATTSSON, J, et al.
(författare)
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OVERLAP LENGTH IN 2-DIMENSIONAL CU(MN) SPIN-GLASS FILMS
- 1993
-
Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 47, s. 14626-14629
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Tidskriftsartikel (refereegranskat)abstract
- Time-dependent dc-magnetization measurements on two-dimensional (2D) Cu(Mn) spin-glass films are reported. Results from the wait-time dependence of the relaxation of the zero-field-cooled magnetization combined with particular effects of temperature cyclings prior to the field application provide evidence for the existence of an overlap length in 2D spin glasses.
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| 32. |
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| 33. |
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| 34. |
- SPASOJEVIC, V, et al.
(författare)
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MAGNETIC-SUSCEPTIBILITY OF THE SEMIMAGNETIC SEMICONDUCTOR HG1-XMNXS
- 1993
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 118, s. 152-158
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic susceptibility of Hg1-xMnxS (x = 0.05, 0.10, 0.20, 0.30) has been measured in a SQUID magnetometer (T = 2-250 K) in a magnetic field of 9 kG. The high-temperature susceptibility of Hg1-xMnxS was found to behave in accordance with the Curie-Weiss law. From chi(T) measurements, for the first time, the microscopic parameter J1/k(B) = -(6.3 +/- 0.1) K (effective exchange integral) has been obtained. A spin S = 2.48 +/- 0.09, close to its atomic value S = 5/2, was also found. Low-temperature susceptibility measurements show that the sample with the highest Mn-concentration (x = 0.30) exhibits a difference between field-cooled and zero-field-cooled susceptibility signalling a spin-glass phase transition at about 4 K. As Hg1-xMnxS is the last uninvestigated alloy from the A1-xIIMnxBVI group, a complete review of experimental values (J1/k(B)) is also given.
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| 35. |
- SRIVASTAVA, BK, et al.
(författare)
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REENTRANT SPIN-GLASS-LIKE BEHAVIOR OF (FE0.90CR0.05NI0.05)2P
- 1994
-
Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 132, s. 124-130
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Tidskriftsartikel (refereegranskat)abstract
- Di-iron phosphide with small substitutions of iron with Cr and Ni, (Fe0.90Cr0.05Ni0.05)2P, has been investigated by SQUID-magnetometry. The sample exhibits a first order ferromagnetic transition at T(c) almost-equal-to 180 K and a re-entrant spin glass transition at T(g) almost-equal-to 125 K. The ferromagnetic transition is severely smeared by weak applied magnetic fields. The re-entrant transition is evidenced from both dc-magnetisation and ac-susceptibility measurements. An aging phenomenon is observed at temperatures below T(g) and the freezing temperatures, T(f), and their corresponding relaxation times, tau scale according to conventional critical slowing down: tau/tau0 = ((T(f) - T(g))/T(g))-znu, with an exponent znu almost-equal-to 9, a value that is found also at ordinary paramagnetic to spin glass transitions.
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