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Long wavelength dynamics of free smectic films

2014 The long wavelength dynamics of monomolecular smectic-A films is studied. Nonlinear nondissipative hydrodynamic equations are derived by means of the Poisson brackets technique. The dissipative terms are constructed, the spectrum of long wavelength modes of the film is found. The transverse sound proves to be anomalously weakly attenuated. The fluctuation contribution to the spectrum is ca...

Incommensurate Spin Dynamics in Underdoped Cuprate Perovskites

The incommensurate magnetic response observed in normal-state cuprate perovskites is interpreted based on the projection operator formalism and the t-J model of Cu-O planes. In agreement with experiment the calculated dispersion of maxima in the susceptibility has the shape of two parabolas with upward and downward branches which converge at the antiferromagnetic wave vector. The maxima are loc...

NQR Study of Dynamics in Incommensurate Phases

Dynamic processes in solids exhibiting structurally incommensurate phases are briefly reviewed, and the application of NMR and NQR is discussed. The unique utility of these methods, arising due to, on one hand, the microscopic resonant nature of the probe used and, on the other, the presence of periodic, though incommensurable, structure , is brought out by presenting recent results in a protot...

On the accuracy of classical and long wavelength approximations for phonon transport in graphene

study of laser angioplasty in visible and long wavelength

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