We report results on epitaxial magnetite (Fe3O4) thin films grown by electron beam ablation on (1 0 0) MgAl2O4 substrates. At 120 K magnetite undergoes a structural and electronic transition, the so-called Verwey transition, at which magnetic and conducting properties of the material change. We observed the Verwey transition on epitaxial films with a thickness of 50 nm by comparing zero-field cooling (ZFC) and field cooling (FC) curves measured with a superconducting quantum interference device (SQUID) magnetometer. Observation of the Verwey transition by SQUID measurements in the films is sign of their high crystalline quality. Room temperature ferromagnetism has also been found by magneto-optical Kerr rotation (MOKE) and confirmed by SQUID measurements, with a hysteresis loop showing a coercive field of hundreds of Oe.
Squid measurement of the Verwey transiotion in epitaxial magnetite thin films / Dediu, V.; Arisi, E.; Bergenti, I.; Riminucci, A.; Solzi, M.; Pernechele, C.; Natali, M.. - In: JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS. - ISSN 0304-8853. - 316:(2007), pp. e721-e723. [10.1016/j.jmmm.2007.03.071]
Squid measurement of the Verwey transiotion in epitaxial magnetite thin films
E. Arisi;I. Bergenti;M. Solzi;C. Pernechele;
2007-01-01
Abstract
We report results on epitaxial magnetite (Fe3O4) thin films grown by electron beam ablation on (1 0 0) MgAl2O4 substrates. At 120 K magnetite undergoes a structural and electronic transition, the so-called Verwey transition, at which magnetic and conducting properties of the material change. We observed the Verwey transition on epitaxial films with a thickness of 50 nm by comparing zero-field cooling (ZFC) and field cooling (FC) curves measured with a superconducting quantum interference device (SQUID) magnetometer. Observation of the Verwey transition by SQUID measurements in the films is sign of their high crystalline quality. Room temperature ferromagnetism has also been found by magneto-optical Kerr rotation (MOKE) and confirmed by SQUID measurements, with a hysteresis loop showing a coercive field of hundreds of Oe.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
