Paramagnetic Meissner effect in high-temperature superconductors

Journal Article · Sun Aug 01 04:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.4030· OSTI ID:5578934

Braunisch, W; Knauf, N; Bauer, G; Kock, A; Becker, A; Freitag, B; Gruetz, A; Kataev, V; Neuhausen, S; Roden, B; Khomskii, D; Wohlleben, D ^[1]; Bock, J; Preisler, E ^[2]

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1. II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln (Germany)
2. Hoechst AG, Werk Knapsack, D-50354 Huerth (Germany)

We have studied the low-field Meissner effect of polycrystalline Bi high-temperature superconductors using a special superconducting-quantum-interference-device magnetometer. In certain samples a surprising feature was observed: Instead of the usual diamagnetic moment a paramagnetic moment develops in the field cooling mode below [ital T][sub [ital c]] for fields [ital H][lt]1 Oe. The data are consistent with orbital paramagnetic moments due to spontaneous currents. Such currents may originate in so-called [pi] contacts in the weak-link network of polycrystalline material. In some of these samples also an anomaly in the low-field microwave absorption was observed, which is obviously correlated with the existence of spontaneous currents.

• OSTI ID: 5578934
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:6; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360207* -- Ceramics
Cermets
& Refractories-- Superconducting Properties-- (1992-)
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
CRYSTALS
CUPRATES
ELECTRONIC EQUIPMENT
EQUIPMENT
FLUXMETERS
HIGH-TC SUPERCONDUCTORS
LEAD ADDITIONS
LEAD ALLOYS
MAGNETISM
MEASURING INSTRUMENTS
MEISSNER-OCHSENFELD EFFECT
MICROWAVE EQUIPMENT
OXIDES
OXYGEN COMPOUNDS
PARAMAGNETISM
PHYSICAL PROPERTIES
POLYCRYSTALS
SQUID DEVICES
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTING DEVICES
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE