The effects of order-parameter strain coupling on the critical (tricritical) sound attenuation and dispersion are studied above T c in the elastically isotropic Ising model. Under free boundary conditions a cross-over in the behaviour of acoustic quantities to a 'strong-coupling' regime is predicted. New scaling relations for the critical attenuation and dispersion are obtained and the corresponding scaling functions are calculated using an ε-expansion. Non-asymptotic effects are also discussed.The effects of order-parameter strain coupling on the critical (tricritical) sound attenuation and dispersion are studied above T c in the elastically isotropic Ising model. Under free boundary conditions a cross-over in the behaviour of acoustic quantities to a 'strong-coupling' regime is predicted. New scaling relations for the critical attenuation and dispersion are obtained and the corresponding scaling functions are calculated using an ε-expansion. Non-asymptotic effects are also discussed.

Journal of Physics Condensed MatterOct 30, 198912 citations

Influence of long-range correlated defects on critical ultrasound propagation in solids

Pavel Vladimirovich Prudnikov, Vladimir V. Prudnikov

The effect of long-range correlated quenched structural defects on the critical ultrasound attenuation and sound velocity dispersion is studied for three-dimensional Ising-like systems. A field-theoretical description of the dynamic critical effects of ultrasound propagation in solids is performed with allowance for both fluctuation and relaxation attenuation mechanisms. The temperature and frequency dependences of the dynamical scaling functions of the ultrasound critical characteristics are calculated in a two-loop approximation for different values of the correlation parameter $a$ of the Weinrib-Halperin model with long-range correlated defects. The asymptotic behavior of the dynamical scaling functions in hydrodynamic and critical regions is separated. The influence of long-range correlated disorder on the asymptotic behavior of the critical ultrasonic anomalies is discussed.The effect of long-range correlated quenched structural defects on the critical ultrasound attenuation and sound velocity dispersion is studied for three-dimensional Ising-like systems. A field-theoretical description of the dynamic critical effects of ultrasound propagation in solids is performed with allowance for both fluctuation and relaxation attenuation mechanisms. The temperature and frequency dependences of the dynamical scaling functions of the ultrasound critical characteristics are calculated in a two-loop approximation for different values of the correlation parameter $a$ of the Weinrib-Halperin model with long-range correlated defects. The asymptotic behavior of the dynamical scaling functions in hydrodynamic and critical regions is separated. The influence of long-range correlated disorder on the asymptotic behavior of the critical ultrasonic anomalies is discussed.

arXiv:0911.2748Physical Review BJul 23, 20099 citations

Attenuation of pulse energy in media with a dispersive absorption line profile

�. V. Lugin, Vladimir M. Mikhailov, Stanislav D. Tvorogov

Russian Physics JournalJan 1, 19720 citations

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of the Weinrib-Halperin model with long-range correlated defects. The asymptotic behavior of the dynamical scaling functions in hydrodynamic and critical regions is separated. The influence of long-range correlated disorder on the asymptotic behavior of the critical ultrasonic anomalies is discussed.