scholarly journals Role of anion size, magnetic moment, and disorder on the properties of the organic conductor κ-(BETS)2Ga1-xFexCl4-yBry

2010 ◽  
Vol 405 (11) ◽  
pp. S295-S298 ◽  
Author(s):  
E. Steven ◽  
H.B. Cui ◽  
A. Kismarahardja ◽  
J.S. Brooks ◽  
D. Graf ◽  
...  
2011 ◽  
Vol 1290 ◽  
Author(s):  
J. K. Mishra ◽  
S. Dhar ◽  
M. A. Khaderabad ◽  
O. Brandt

ABSTRACTGd:GaN layers grown with different Gd concentrations by molecular beam epitaxy (MBE) are studied using photoconductivity and photo-thermoelectric power spectroscopy. Our study reveals that the incorporation of Gd produces a large concentration of acceptor-like defects in the GaN lattice. The defect band is found to be located ~450meV above the valence band. Moreover, the concentration of defects is found to increase with the Gd concentration. The effect of annealing on the structural and the magnetic properties of GaN implanted with Gd is also investigated. A clear correlation between the saturation magnetization and the defect density is observed in implanted samples. The colossal magnetic moment per Gd ion and the ferromagnetism observed in this material is explained in terms of the formation of giant defect cluster around each Gd ion.


2004 ◽  
Vol 18 (25) ◽  
pp. 3343-3353 ◽  
Author(s):  
COLIN BENJAMIN ◽  
A. M. JAYANNAVAR

Amperes law states that the magnetic moment of a ring is given by current times the area enclosed. Also from equilibrium statistical mechanics, it is known that magnetic moment is the derivative of free energy with respect to magnetic field. In this work, we analyze a quantum double ring system interacting with a reservoir. A simple S-Matrix model is used for system-reservoir coupling. We see complete agreement between the aforesaid two definitions when coupling between system and reservoir is weak, increasing the strength of coupling parameter, however, leads to disagreement between the two, thereby signifying the important role played by the coupling parameter in mesoscopic systems.


2011 ◽  
Vol 170 ◽  
pp. 74-77 ◽  
Author(s):  
Kazimierz Łątka ◽  
Jacek Gurgul ◽  
Andrzej W. Pacyna ◽  
Rainer Pöttgen

The results of magnetic studies and Mössbauer investigations made with 119Sn source are reviewed for the series of RERhSn (RE = Tb, Dy and Ho) compounds crystallizing in the same hexagonal ZrNiAl-type of structure. The role of crystalline electric field effects in the establishing of magnetic moment orientations observed in these compounds and their influence on the observed magnitudes of magnetic moments are discussed.


2016 ◽  
Vol 4 (1) ◽  
pp. 65-75 ◽  
Author(s):  
Dominique de Caro ◽  
Christophe Faulmann ◽  
Lydie Valade ◽  
Kane Jacob ◽  
Benoit Cormary

Ionic liquids are used for controlling the growth of organic conductors as nanoparticles. We review the conditions of preparation of nanoparticles of conductors derived from tetrathiafulvalene (TTF), tetramethyltetraselenafulvalene (TMTSF) and bis-ethylenedithiotetrathiafulvalene (BEDT-TTF). They are prepared by electrocrystallization using an ionic liquid supporting electrolyte in which the cation plays the role of growth controller and the anion enters the composition of the expected organic conductor. Stable suspensions of nanoparticles are obtained in one case, a valuable characteristic for potential applications in electronic devices.


2011 ◽  
Vol 18 (2) ◽  
pp. 235-241 ◽  
Author(s):  
A. K. Nekrasov ◽  
F. Z. Feygin

Abstract. We consider the action of the ponderomotive force of low-frequency Alfvén waves on the distribution of the background plasma. It is assumed that the ponderomotive force for traveling waves arises as a result of the background inhomogeneity of medium under study. Expressions for the ponderomotive force obtained in this paper differ from previous analogous results. The induced magnetic moment of medium is taken into account. It is shown that the well-known Pitayevsky's formula for the magnetic moment is not complete. The role of the induced nonlinear thermal pressure in the evolution of the background plasma is considered. We give estimations for plasma displacement due to the long- and short-acting nonlinear wave perturbations. Some discussion of the ponderomotive action of standing waves is provided.


1993 ◽  
Vol 313 ◽  
Author(s):  
Akimasa Sakuma ◽  
Yutaka Sugita

ABSTRACTThe spin-polarized band calculations for the iron nitrides, Fe3N, Fe4N and Fe16N2, have been performed with use of LMTO-ASA Method in the frame of local spin density functional formalism. The results show that the most distant Fe atoms from N have the largest magnetic moment. The central role of the N atom is to bring about the large magnetic moments through the lattice expansion. Concurrently, the N atoms promote an itinerancy of electrons and then in turn prevent the exchange-splitting. This results in an Fe16N2 with the lowest N concentration having the largest magnetic moments. Quantitatively, the obtained magnetic moments are in fair agreements with the experimental results except for Fe16Nr The calculated magnetic moment of Fe6N2 is about 2.4 ΜB/Pε, while the measured value is reported as 3.5 ΜB/FB. The orbital magnetic moment of Fe16N2 is about 0.07 ΜB, which is too small to make up for the difference from the experimental value.


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