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Multilayers

Christian Binek

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Full-Text Articles in Physics

Ac Susceptibility Studies Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek Mar 2012

Ac Susceptibility Studies Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek

Christian Binek

Discontinuous metal–insulator multilayers [Co80Fe20(t)/Al2O3(3 nm)]10 are prepared by ion-beam sputtering and investigated by SQUID magnetometry and previous AC susceptometry. For 1.0less-than-or-equals, slanttless-than-or-equals, slant1.6 nm, two coexisting subsystems of dipolar coupled nanoparticles are encountered. While a spin-glass-like freezing particulate fraction dominates at t=1.0 nm, a percolating dipolar ferromagnetic fraction becomes increasingly important at higher nominal thickness of t.


Magnetic States Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek Mar 2012

Magnetic States Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek

Christian Binek

Discontinuous metal–insulator multilayers [Co80Fe20(t)/Al2O3(3 nm)]n were studied by SQUID magnetometry and AC susceptometry. CoFe forms ferromagnetic particles in the Al2O3 matrix. In this paper, we focus on the field dependence of the AC susceptibility of samples with t=1.3 nm. We find strong evidence for transitions from a superpara- to a superferromagnetic and, finally, to a reentrant superspin glass previous state.