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RESEARCH PRODUCT
Analysis of magnetization relaxation in MgB2 bulk samples obtained by electric-field assisted sintering
Gerhard JakobH. AdrianJ. R. GrozaL. MiuDana MiuPetre BadicaGheorghe AldicaI. Ivansubject
Materials scienceCondensed matter physicsMagnetometerRelaxation (NMR)Energy Engineering and Power TechnologySinteringCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsMagnetic fieldlaw.inventionSQUIDMagnetizationCreeplawCondensed Matter::SuperconductivityElectric fieldElectrical and Electronic Engineeringdescription
Abstract The relaxation of the irreversible magnetization of MgB2 bulk samples obtained by electric-field assisted sintering was investigated using the SQUID magnetometry for a magnetic field H up to 50 kOe applied in zero-field-cooling conditions. We observed a crossover plastic creep at high temperatures T-elastic creep at low T, described by H ∝ T−2 in the low T range, which appears to be caused by the macroscopic currents induced in the sample during magnetization measurements. By decreasing T below this line the determined creep exponent rapidly overcomes the widely accepted theoretical values for elastic (collective) pinning. This behaviour can easily be explained through the occurrence of micro flux jumps, leading to a finite magnetization relaxation rate in the low-T limit.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-11-01 | Physica C: Superconductivity |