One-dimensional Superdiffusive Heat Propagation Induced by Optical Phonon-Phonon Interactions

Abstract

It is known that one-dimensional anomalous heat propagation is usually characterized by a Lévy walk superdiffusive spreading function with two side peaks located on the fronts due to the finite velocity of acoustic phonons, and in the case when the acoustic phonons vanish, e.g., due to the phonon-lattice interactions such that the system's momentum is not conserved, the side peaks will disappear and a normal Gaussian diffusive heat propagating behavior will be observed. Here we show that there exists another type of superdiffusive, non-Gaussian heat propagation but without side peaks in a typical nonacoustic, momentum-nonconserving system. It implies that thermal transport in this system disobeys the Fourier law, in clear contrast with the existing theoretical predictions. The underlying mechanism is related to a novel effect of optical phonon-phonon interactions. These findings may open a new avenue for further exploring thermal transport in low dimensions.

6 pages, 5 figures+Supplementary Material; The title has been changed and the presentation has been improved

References in corpus (12)

• Length-dependent thermal conductivity in suspended single-layer graphene
• Heat Transport in low-dimensional systems
• Lévy walks
• A momentum conserving model with anomalous thermal conductivity in low dimension
• Local Temperature and Universal Heat Conduction in FPU chains
• Normal Heat Conduction in a Chain with Weak Interparticle Anharmonic Potential
• Crossover from ballistic to normal heat transport in the ${\varphi }^4$ lattice: If nonconservation of momentum is the reason, what is the mechanism?
• Heat transport via low-dimensional systems with broken time-reversal symmetry
• Large-deviations for spatial diffusion of cold atoms
• Observing Golden Mean Universality Class in the Scaling of Thermal Transport
• Heat perturbations spreading in the Fermi-Pasta-Ulam-$\beta$ system with next-nearest-neighbor coupling: Competition between phonon dispersion and nonlinearity
• Some thermal transport properties of the FPU model with quadratic pinning

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• A general multi-wave quasi-resonance theory for lattice energy diffusion