Relaxation dynamics of multi-level tunneling systems

P. Neu; A. Heuer

doi:10.1063/1.473313

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arXiv · cond-mat/9610179

Relaxation dynamics of multi-level tunneling systems

P. Neu·A. Heuer

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Abstract

A quantum mechanical treatment of an asymmetric double-well potential (DWP) interacting with a heat bath is presented for circumstances where the contribution of higher vibrational levels to the relaxation dynamics cannot be excluded from consideration. The deep quantum limit characterized by a discrete energy spectrum near the barrier top is considered. The investigation is motivated by simulations on a computer glass which show that the considered parameter regime is ``typical'' for DWPs being responsible for the relaxation peak of sound absorption in glasses. Relaxation dynamics resembling the spatial- and energy-diffusion-controlled limit of the classical Kramers' problem, and Arrhenius-like behavior is found under specific conditions.

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P. Neu, A. Heuer. 1996-10-24. Relaxation dynamics of multi-level tunneling systems. https://doi.org/10.1063/1.473313

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