Microsoft word - abstract-2b_.doc

Abstract for IV Euro-Asian Symposium “Trends in MAGnetism”: Nanospintronics.
EASTMAG – 2010,
June 28 – July 2, 2010, Ekaterinburg, Russia
[email protected]
MAGNETIC AND DIELECTRIC PROPERTIES OF NANOPHASE MANGANESE ZINC
SUBSTITUTED LITHIUM FERRITE
E. De Fazio1 , P. Bercoff 2 and S.E. Jacobo1*
1LAFMACEL, Facultad de Ingeniería, Universidad de Buenos Aires Paseo Colón 850 (1063), 2 FAMAF, Universidad de Córdoba, IFEG-Conicet, Cdad Universitaria (5000) Lithium and substituted lithium ferrites have been found to be excellent materials in high density recording media, absorbers and microwave devices due to their low cost, high saturation magnetization, high Curie temperature and hysteresis loop properties, which offer advantageous performance over other spinel structures [1-4]. Nanocrystalline manganese zinc substituted lithium ferrites Li0.5xMn0.4Zn0.6-xFe2+0.5xO4 (Table 1) were prepared by the sol-gel autocombustion method. All samples were calcined at 1100ºC for two hours in nitrogen. Magnetic properties were measured by vibrating sample magnetometer. Microwave properties (permeability and permitivity) were measured on a HP4291A Material Analyser from 1-1800 MHz. X-ray diffraction analysis confirmed that samples are monophasic and that only spinel phase is present for x<0.4. The cell parameter of the cubic phase decreases with the concentration of lithium. The average size is in the order of 80 nm. The variation of saturation magnetization was studied as a function of lithium content. All the compositions indicate that they are ferrimagnetic in nature. frequency (Hz)
Permeabilty of Li0.5xMn0.4Zn0.6-xFe2+0.5xO4 1MHz- 1.8GHz The dielectric constant, dielectric loss tangent and ac conductivity of all samples were measured at room temperature as a function of frequency. Permeability increases with substitution while permitivity shows small variation in the measured frequency range. Lithium substitution plays an important role in changing the structural and magnetic properties of these MnZn ferrites. [1] J. Qiu, L. Lan, H. Zhang, M. Gu, J. Alloy. Compd. 453 (2008) 261. [2] Y. Yang, B. Zhang, W. Xu, Y. Shi, Z. Jiang, N. Zhou, B. Gu, H. Lu, J. Magn. Magn. Mater. 256 (2003) 129 [3] S. Sugimoto, K. Haga, T. Kagotani, K. Inomata, J. Magn. Magn. Mater. 290-291 (2005) 1188 [4] C. Sun, K. Sun, Physica B. 391 (2007) 335 Abstract for IV Euro-Asian Symposium “Trends in MAGnetism”: Nanospintronics.
EASTMAG – 2010,
June 28 – July 2, 2010, Ekaterinburg, Russia
[email protected]
(please use the separate page or include this info in the body of your e-maul message)
Corresponding Author:
Title*__________________(Dr., Prof.)
Family Name* _______________ (Jacobo)
Given Name* ________________ (Silvia Elena)
Place of work*_______________(Facultad de Ingeniería-Universidad de Buenos Aires)
Street*__________________(Paseo Colón 850)
City*__________________( Capital Federal)
Region *__________________(Buenos Aires)
Postal code*__________________(1063)
Country*__________________(Argentina)
e-mail address* [email protected]_________
Phone *__________________(example +54 11-4343-0891)
FAX *__________________(example +54 11-4343-0126)
The subject of my presentation fits the following category (select one)*
A_Spin polarized transport
B_Spin Dynamics, Spin Waves, Spin-Wave Resonance
C_Spin Reorientation Phase Transitions
D_Spin-Orbit and Exchange Interactions, Magnetic Anisotropy and Magnetostriction
E_Dynamics of Domain Structures and Domain Walls
F_Magnetic Nanostructures and Films
G_Magnetism and Nanomaterials
H_Low-Dimensional Magnetism
I_Magnetism of Strongly Correlated Systems
J_Magnetotransport and Magnetooptics

Preferred type of presentation*_______________________(Oral/Poster)

Source: http://laboratorios.fi.uba.ar/lafmacel/img/Abstract2b.pdf