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arXiv · 1911.12921

Ultrafast dynamics in the Lifshitz-type 5${d}$ pyrochlore antiferromagnet Cd$_{2}$Os$_{2}$O$_{7}$

Inho Kwak·Min-Cheol Lee·Byung Cheol Park·Choong H. Kim·Bumjoo Lee·C. W. Seo·J. Yamaura·Z. Hiroi·Tae Won Noh·K. W. Kim
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Abstract

We investigate the ultrafast dynamics of Cd$_2$Os$_2$O$_7$, a prototype material showing a Lifshitz-type transition as a function of temperature. In the paramagnetic metallic state, the photo-reflectivity shows a sub-picosecond relaxation, followed by a featureless small offset. In the antiferromagnetic state slightly below $T_N$, however, the photo-reflectivity resurges over hundreds of picoseconds, which goes beyond the usual realm of the effective-temperature model. Our observations are consistent with the Lifshitz phase transition of Cd$_2$Os$_2$O$_7$ driven by the evolution of the local magnetic moment.

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Inho Kwak, Min-Cheol Lee, Byung Cheol Park, Choong H. Kim, Bumjoo Lee, C. W. Seo, J. Yamaura, Z. Hiroi, Tae Won Noh, K. W. Kim. 2019-11-29. Ultrafast dynamics in the Lifshitz-type 5${d}$ pyrochlore antiferromagnet Cd$_{2}$Os$_{2}$O$_{7}$. https://doi.org/10.1103/physrevb.100.144309

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