paper

Optical spectroscopy study of charge density wave order in Sr $_{3}$ Rh $_{4}$ Sn $_{13}$ and (Sr $_{0.5}$ Ca $_{0.5}$ ) $_{3}$ Rh $_{4}$ Sn $_{13}$

arXiv:1609.04206 · doi:10.1007/s11433-017-9007-0

Abstract

We perform optical spectroscopy measurement across the charge density wave (CDW) phase transitions on single-crystal samples of Sr $_{3}$ Rh $_{4}$ Sn $_{13}$ and (Sr $_{0.5}$ Ca $_{0.5}$ ) $_{3}$ Rh $_{4}$ Sn $_{13}$ . Formation of CDW energy gap was clearly observed for both single-crystal samples when they undergo the phase transitions. The existence of a Drude component in $I ¨ _{1} (I ¨ )$ below \TCDW indicates that the Fermi surface is only partially gapped in the CDW state. The obtained value of 2 $I^$ /K $_{B}$ T $_{C D W}$ is roughly 13 for both Sr $_{3}$ Rh $_{4}$ Sn $_{13}$ and (Sr $_{0.5}$ Ca $_{0.5}$ ) $_{3}$ Rh $_{4}$ Sn $_{13}$ compounds. The value is considerably larger than the mean-field value based on the weak-coupling BCS theory. The observed spectral feature in (Sr $_{x}$ Ca $_{1 - x}$ ) $_{3}$ Rh $_{4}$ Sn $_{13}$ resembles those seen in many other CDW systems.

Optical spectroscopy study of charge density wave order in Sr3​Rh4​Sn13​ and (Sr0.5​Ca0.5​)3​Rh4​Sn13​

Abstract

Optical spectroscopy study of charge density wave order in Sr $_{3}$ Rh $_{4}$ Sn $_{13}$ and (Sr $_{0.5}$ Ca $_{0.5}$ ) $_{3}$ Rh $_{4}$ Sn $_{13}$