Paramagnetic Meissner effect in high-temperature superconductors

Autor:	J. Bock, Vladislav Kataev, W. Braunisch, B. Roden, S. Neuhausen, A. Becker, A. Grütz, A. Kock, E. Preisler, B. Freitag, Gernot Bauer, N. Knauf, D. Wohlleben, D. I. Khomskii
Rok vydání:	1993
Předmět:	Superconductivity Physics Magnetization Paramagnetism High-temperature superconductivity Magnetic moment Condensed matter physics law Meissner effect Condensed Matter::Superconductivity Diamagnetism Absorption (logic) law.invention
Zdroj:	Physical Review B. 48:4030-4042
ISSN:	1095-3795 0163-1829
DOI:	10.1103/physrevb.48.4030
Popis:	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 ${\mathit{T}}_{\mathit{c}}$ for fields H1 Oe. The data are consistent with orbital paramagnetic moments due to spontaneous currents. Such currents may originate in so-called \ensuremath{\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.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::13c40dec93a86ffe3bce98752ee6ed4f https://doi.org/10.1103/physrevb.48.4030 Zobrazit plný text záznamu