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Chemomagnetism, magnetoconcentration effect and "fishtail" anomaly in chemically-induced granular superconductors

Sergei Sergeenkov
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Abstract

Within a 2D model of Josephson junction arrays (created by 2D network of twin boundary dislocations with strain fields acting as insulating barrier between hole-rich domains in underdoped crystals), a few novel effects expected to occur in intrinsically granular material are predicted including: (i) Josephson chemomagnetism (chemically induced magnetic moment in zero applied magnetic field) and its influence on a low-field magnetization (chemically induced paramagnetic Meissner effect), and (ii) magnetoconcentration effect (creation of oxygen vacancies in applied magnetic field) and its influence on a high-field magnetization (chemically induced analog of "fishtail" anomaly). The conditions under which these effects can be experimentally measured in non-stoichiometric high-T_c superconductors are discussed.

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Sergei Sergeenkov. 2002-12-20. Chemomagnetism, magnetoconcentration effect and "fishtail" anomaly in chemically-induced granular superconductors. https://doi.org/10.1134/1.1564227

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