studies of the magnetization of fe2o3@pt nanoparticles at room temperature showed that there is superparamagnetic contribution with high saturation magnetization about 12.35(emu/g), and soft ferromagnetic contribution with narrow coercive field about 58(oe). in this paper we fitted the hystersis loop of sample with brillouin function that demonstrating existence of superparamagnetic phase. tota...

Studies of the magnetization of Fe2O3@Pt nanoparticles at room temperature showed that there is superparamagnetic contribution with high saturation magnetization about 12.35(emu/g), and soft ferromagnetic contribution with narrow coercive field about 58(Oe). In this paper we fitted the hystersis loop of sample with Brillouin function that demonstrating existence of superparamagnetic phase. Tota...

In this paper energy bands and Berry curvature of graphene was studied. Desired Hamiltonian regarding the next-nearest neighbors obtained by tight binding model. By using the second quantization approach, the transformation matrix is calculated and the Hamiltonian of system is diagonalized. With this Hamiltonian, the band structure and wave function can be calculated. By using calculated wave f...

The Brillouin shift and width for poly(acrylic acid) hydrogels have been obtained as a function of gel network volume fraction using a five-pass Fabry-Pdrot interferometer. A conspicuous peak has been observed in the Brillouin shift at high volume fraction. The results are discussed in the light of a theory for the Brillouin light-scattering from gels proposed by Marqusee and Deutch-

in this paper energy bands and berry curvature of graphene was studied. desired hamiltonian regarding the next-nearest neighbors obtained by tight binding model. by using the second quantization approach, the transformation matrix is calculated and the hamiltonian of system is diagonalized. with this hamiltonian, the band structure and wave function can be calculated. by using calculated wave f...

In this paper energy bands and Berry curvature of graphene was studied. Desired Hamiltonian regarding the next-nearest neighbors obtained by tight binding model. By using the second quantization approach, the transformation matrix is calculated and the Hamiltonian of system is diagonalized. With this Hamiltonian, the band structure and wave function can be calculated. By using calculated wave f...

2014 On the basis of the Landau and Lifshitz criteria, the allowed symmetries of soft-modes in the cubic crystals having space-groups Oih (i = 1, 2, ...,10) are presented explicitly. All single valued representations for high-symmetry points in the three different Brillouin zones of the cubic system (P, F, I) have been investigated. Our results are compared with those of other authors. J. Physi...

The experimental results of the Brillouin shift and width for poly(vinyl alcohol) and poly(vinyl chloride) gels as a function of gel network volume fraction have been analysed using the theory of Marqusee and Deutch for Brillouin light-scattering from polymer gels, incorporated with a new plausible assumption relating the speed of sound in the gel network with its volume fraction. It has been f...

We evaluate the Brillouin frequency shift (BFS) determination error when utilizing the Brillouin phase spectrum (BPS) instead of the Brillouin gain spectrum (BGS) in BOTDA systems. Systems based on the BPS perform the determination of the BFS through a linear fit around the zero de-phase frequency region. An analytical expression of the error obtained in the BFS determination as a function of t...