Nonasymptotic Effects in Critical Sound Propagation Associated with Spin-Lattice Relaxation
| dc.creator | Pawlak, Andrzej | |
| dc.date | 1999-03-15 | |
| dc.date.accessioned | 2026-07-07T03:13:02Z | |
| dc.date.available | 2026-07-07T03:13:02Z | |
| dc.description | The nonasymptotic critical behavior of sound attenuation coefficient has been studied in an elastically isotropic Ising system above the critical point on the basis of a complete stochastic model including both spin-energy and lattice-energy modes linearly coupled to the longitudinal sound mode. The effect of spin-lattice relaxation on the ultrasonic attenuation is investigated. The crossover between weak-singularity behavior $t^{-2 α}$ and strong singularity behavior $t^{-(z ν+α)}$ is studied. A new high-frequency regime with singularity of the type $t^{-z ν+α}$ is discovered in the magnetic systems. This new regime corresponds to an adiabatic sound propagation and is very similar to the ones in binary mixture and liquid helium. A new frequency-dependent specific-heat being the harmonic average of the bare lattice and critical spin specific-heats is introduced. It was shown that such specific-heat descibes the process of equilibrization between spin and lattice subsystems and includes the most important features of critical sound attenuation. In some regions of coupling constants the acoustic self-energy can be very well approximated solely by this quantity. | |
| dc.description | RevTeX, 14 pages | |
| dc.identifier | https://arxiv.org/abs/cond-mat/9903229 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/9903229 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/29141 | |
| dc.subject | Statistical Mechanics | |
| dc.title | Nonasymptotic Effects in Critical Sound Propagation Associated with Spin-Lattice Relaxation | |
| dc.type | text |