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arXiv · 1402.6104

Unusual Two-stage Dynamics of the Spin-Lattice Polaron Formation

Jan Kogoj·Zala Lenarcic·Denis Golez·Marcin Mierzejewski·Peter Prelovsek·Janez Bonca
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Abstract

We follow the formation of a spin-lattice polaron after a quantum quench that simulates absorption of the pump{pulse in the time-resolved experiments. We discover a two-stage relaxation where spin and lattice degrees of freedom represent an integral part of the relaxation mechanism. In the first stage the kinetic energy of the spin-lattice polaron relaxes towards its ground state value while relaxation processes via spin and phonon degrees of freedom remain roughly independent. In the second, typically much longer stage, a subsequent energy transfer between lattice and spin degrees of freedom via the charge carrier emerges. The excess local spin energy radiates away via magnon excitations.

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Jan Kogoj, Zala Lenarcic, Denis Golez, Marcin Mierzejewski, Peter Prelovsek, Janez Bonca. 2014-02-25. Unusual Two-stage Dynamics of the Spin-Lattice Polaron Formation. https://doi.org/10.1103/physrevb.90.125104

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