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arXiv · 1802.02934

Anomalous phonon lifetime shortening in paramagnetic CrN caused by magneto-lattice coupling: A combined spin and ab initio molecular dynamics study

Irina Stockem·Anders Bergman·Albert Glensk·Tilmann Hickel·Fritz Körmann·Blazej Grabowski·Jörg Neugebauer·Björn Alling
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Abstract

We study the mutual coupling of spin fluctuations and lattice vibrations in paramagnetic CrN by combining atomistic spin dynamics and ab initio molecular dynamics. The two degrees of freedom are dynamically coupled leading to non-adiabatic effects. Those effects suppress the phonon life times at low temperature compared to an adiabatic approach. The here identified dynamic coupling provides an explanation for the experimentally observed unexpected temperature dependence of the thermal conductivity of magnetic semiconductors above the magnetic ordering temperature.

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Irina Stockem, Anders Bergman, Albert Glensk, Tilmann Hickel, Fritz Körmann, Blazej Grabowski, Jörg Neugebauer, Björn Alling. 2018-02-08. Anomalous phonon lifetime shortening in paramagnetic CrN caused by magneto-lattice coupling: A combined spin and ab initio molecular dynamics study. https://doi.org/10.1103/physrevlett.121.125902

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