Exchange Bias in Iron-Oxide Particles Nanocasted in Periodic Porous Silica |
| A. Zeleňáková a, J. Kováč b and V. Zeleňák c
a Department of Solid State Physics, University of P.J. Šafárik, Park Angelinum 9, 041 54 Košice, Slovakia b Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Košice, Slovakia, c Department of Inorganic Chemistry, University of P.J. Šafárik, Moyzesova 51, 041 54 Košice, Slovakia |
| Full Text PDF |
| Iron-oxide nanoparticles were nanocasted in the periodic mesoporous silica matrix, consisting of two-dimensional hexagonally ordered channel system with the mean diameter of the channels about 7 nm. The magnetic measurements of dc magnetization confirm behavior typical of a superparamagnetic system, such as the irreversibility of the zero-field-cooled and field-cooled curves, presence of a maximum in zero-field-cooled curve related with blocking temperature TB and revealing of coercivity HC below TB. The existence of negative exchange bias effect below TB was confirmed in our system represented by value of exchange bias field HEB=-970 Oe measured at the temperature 2 K. |
| DOI: 10.12693/APhysPolA.115.357 PACS numbers: 61.46.Df, 68.37.Lp, 75.20.-g, 75.30.Cr |