We report the first measurement of contributions from multipole moments higher than the dipole of a non-uniformly magnetized intermediate state of a type I superconductor. In the specimen shape studied, these contributions are small compared to that from the dipole and they do not affect in a significant way the magnetization curve obtained using a commercial SQUID magnetometer. © 1990.

Sankaranarayanan V

Department Of Physics

C. K. Subramanian

Magnetometers

MAGNETIZATION CURVE

MULTIPOLE MOMENTS

SQUID MAGNETOMETER

TYPE I SUPERCONDUCTOR

TYPE II SUPERCONDUCTOR

Superconducting materials

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IIT Madras

Measurement of higher multipole moments of an inhomogeneous state of a superconductor

Solid State Communications

The results of experimental studies on hysteresis in magnetization, thermomagnetic history effects, anomalous variations in magnetic hysteresis curves and the decay rates of magnetization obtained under different thermomagnetic histories in specimens of conventional and high temperature superconductors are presented. The Bean's critical state model is considered adequate to explain magnetic behaviour in conventional hard superconductors. The similarity in the general features of the results of different experiments on specimens of the two families of superconductors underscores the efficacy of the said model to understand some aspects of the macroscopic magnetic response of high temperature superconductors as well. For instance, the isothermal magnetization hysteresis loop which comprises of magnetization curves along forward (-Hmax to +Hmax) and reverse (+Hmax to -Hmax) paths define an envelop within which all isothermal magnetization data along different thermomagnetic histories lie. There exist inequality relationship between various field values identified as Hpeak, HI, HII etc. in isothermal magnetization hysteresis as well as magnetic relaxation data. The entire field span of an isothermal magnetization hysteresis data set can be considered to comprise of three parts corresponding to (Mrem(H)-MFC(H)+MZFC(H)) being equal to, less than or greater than zero, where Mrem(H) are the remanent magnetization values obtained on reducing field to zero after having the specimen in different applied field (H) values. There are, however some situations amongst thermomagnetic history effects in specimens which show incomplete flux trapping on field cooling, where the critical state model has been found inadequate. © 1992 Indian Academy of Sciences.

Pramana

Magnetization studies in niobium and YBa2Cu3O7 samples

Zero-field-cooled (ZFC) and field-cooled (FC) magnetization data for fields applied parallel and perpendicular to the plane of flat superconducting Pb discs (Tc=7.2 K) are presented. A quasi-irreversibility temperature T*, which differs for the two orientations, can be identified in these data. T* is found to vary with the field approximately as (1-T*/Tc)H1.085. © 1991 The American Physical Society.

Physical Review B

Quasi-irreversibility temperature in a type-I superconductor

Superconductivity

The Intermediate State in Type I Superconductors

David Mattingly

Effect of a geometrical length scale on remanent magnetization and critical currents in Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O crystals

Magnetization curves of hard superconductor samples with non-zero demagnetization factor

Physical Review Letters

Direct Macroscopic Observation of Antiferromagnetic Order in Zero Applied Field

Journal	Solid State Communications
ISSN	00381098
Open Access	No