Search results for "CONDENSED MATTER"
showing 10 items of 13918 documents
Normal-Metal–Insulator–Superconductor Tunnel Junction With Atomic-Layer-Deposited Titanium Nitride as Superconductor
2015
Enhanced Debye level in nano Zn1+xSb, FeSb2, and NiSb: Nuclear inelastic spectroscopy on121Sb (Phys. Status Solidi B 5/2014)
2014
One‐magnon Raman scattering in Ni c Mg 1–c O solid solutions
2005
The one-magnon Raman scattering was studied for the first time in antiferromagnetic NicMg1–cO solid solutions as a function of temperature and composition. We found that (i) the one-magnon frequency extrapolated to T = 0 K experiences an abrupt change between c = 0.99 and c = 0.9 and (ii) the one-magnon energy for highly diluted nickel oxide vanishes significantly below the Neel temperature. The obtained dependences are compared to the theoretical predictions within the mean field approximation. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Beyond the spin model: exchange coupling in molecular magnets with unquenched orbital angular momenta.
2011
In this critical review we review the problem of exchange interactions in polynuclear metal complexes involving orbitally degenerate metal ions. The key feature of these systems is that, in general, they carry an unquenched orbital angular momentum that manifests itself in all their magnetic properties. Thus, interest in degenerate systems involves fundamental problems related to basic models in magnetism. In particular, the conventional Heisenberg-Dirac-Van Vleck model becomes inapplicable even as an approximation. In the first part we attempt to answer two key questions, namely which theoretical tools are to be used in the case of degeneracy, and how these tools can be employed. We demons…
Study of thermoelectric magnetohydrodynamic convection on solute redistribution during laser additive manufacturing
2020
Abstract Melt pools formed in laser additive manufacturing (AM) are subject to large thermal gradients, resulting in the formation of thermoelectric currents due to the Seebeck effect. When in the presence of an external magnetic field, a Lorentz force is formed which drives fluid flow in the melt pool. This Thermoelectric Magnetohydrodynamics (TEMHD) phenomenon, can have a significant impact on the melt pool morphology and can alter the microstructural evolution of the solidification process. By coupling steady-state mesoscopic melt pool calculations to a microscopic solidification model, predictions of the resulting microstructure for multiple deposited layers have been obtained. The resu…
Vibrational properties of semiconductor nanowires and nanowire heterostructures: ensembles and single nanowires
2013
Erratum to ‘Raman spectroscopy of β-irradiated silica glass’ by B. Boizot, S. Agnello, B. Reynard, R. Boscaino and G. Petite [J. Non-Cryst. Solids 32…
2004
Theoretical investigation of the electronic structure of fullerenes
1994
Summary form only given. Research in the growing family of fullerene compounds are in continuous expansion. Much theoretical and experimental effort has been devoted to the study of the electronic properties these carbon cages present. However, although significant work has been done, the purpose of this paper is to provide a detailed theoretical analysis of the electronic properties of several fullerenes. We have calculated the electronic structure of these carbon cages within the valence effective Hamiltonian (VEH) approach. The calculated one-electron energy levels are correlated with experimental UPS spectra. The good correlation between calculated and experimental values shows VEH appr…
Phonon Deformation Potentials from Raman Measurements on Semiconductor Membranes
1997
Spin-lattice relaxation of deuterated methyl groups: Implications of the pauli principle
1999
The high-field spin-lattice relaxation of deuterated methyl groups undergoing rotational tunneling is investigated theoretically. It is found that for systems showing a tunneling frequency comparable to accessible Larmor frequencies the relaxation to equilibrium of the Zeeman energy does not follow a simple exponential time dependence even in powdered samples due to a finite coupling to the relaxation of the tunneling system. This finding contrasts to the high-temperature behavior of reorienting methyl groups which undergo simple exponential relaxation. The nonexponentiality has its origin in the statistical coupling of the three deuteron spins due to the Pauli principle.