The Study of Anisotropy and Domain Condition of Permalloy Thin Films

Authors A.V. Morozov1, V.P. Alekseev1, V.A. Naumov2, V.V. Morozov3,

1 Yaroslavl State University, 14, Soviet Str., Yaroslavl, Russia

2 Yaroslavl Branch of the Institute of Physics and Technology of RAS, 21, Universitetskaya Str., Yaroslavl region, Yurievskoye, Russia

3 Yaroslavl State Technical University, 88, Moscow Ave., Yaroslavl, Russia

Issue Volume 5, Year 2013, Number 4
Dates Received 01 October 2013; revised manuscript received 10 November 2013; published online 10 December 2013
Citation A.V. Morozov, V.P. Alekseev, V.A. Naumov, et al., J. Nano- Electron. Phys. 5 No 4, 04016 (2013)
PACS Number(s) 75.70.Ak, 75.50.Bd
Keywords Permalloy thin films, Magnetometer, Hysteretic loop, Coercive force (2) , Single-domain particles, Superparamagnetic state.
Annotation Hysteretic Loops, 1,5; 3,0; 4,5; 6 and 10 nm in thickness, obtained by magnetron sputtering of Ni81Fe19 alloy, were measured by means of vibration magnetometer. It has been detected that by increasing the film thickness from 3 to 10 nm coercive force (HC) increases as well. In the direction perpendicular to the axis of easy magnetization the loop form considerably differs from the right-angled one, which is caused by amplitude dispersion of anisotropy. The films, derived in scattered magnetic field of the Earth, are by magnetic parameter isotropic. The results of atomic force microscope investigation indicate to the granular structure of films and confirms the presence of non-magnetized areas among the examined films. The critical thickness at which permalloy films pass from multi-domain to single-domain state was 10 nm. Estimation of the critical thickness of the transition from single-domain state to superparamagnetic led to the values of 1.5-2 nm.

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