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arXiv · 1908.04479

Evidence of structural evolution in Sr2RhO4 studied by time-resolved optical reflectivity spectroscopy

Min-Cheol Lee·Inho Kwak·Choong H. Kim·Bumjoo Lee·Byung Chul Park·Junyoung Kwon·Wonshik Kyung·Changyoung Kim·Tae Won Noh·Kyungwan Kim
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Abstract

We investigate ultrafast dynamics from photoinduced reflectivity of Sr2RhO4 by using femtosecond near-infrared pulses. We observe a clear temperature-dependent anomaly in its electronic dynamics which slows down below 160 K. In addition, coherent oscillations of the A1g symmetric 5.3-THz phonon exhibit a 90-degree shift in its initial phase across TS, indicating a structural change in octahedral rotation distortions. We propose that octahedral structure in Sr2RhO4 evolves at around TS, and it can influence on the non-equilibrium dynamics of photoinduced carriers as well as real-time phonon responses.

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Min-Cheol Lee, Inho Kwak, Choong H. Kim, Bumjoo Lee, Byung Chul Park, Junyoung Kwon, Wonshik Kyung, Changyoung Kim, Tae Won Noh, Kyungwan Kim. 2019-08-13. Evidence of structural evolution in Sr2RhO4 studied by time-resolved optical reflectivity spectroscopy. https://doi.org/10.1103/physrevb.100.235139

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