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Optical evidence for mass enhancement of quasiparticles in pyrochlore Cd$_2$Re$_2$O$_7$

N. L. Wang·J. J. McGuire·T. Timusk·R. Jin·J. He·D Mandrus
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Abstract

We report on the results of optical studies of the newly discovered superconductor Cd$_2$Re$_2$O$_7$ in the normal state. We show that the compound has an exotic metallic state at low temperature. The optical conductivity spectrum exhibits two distinct features: a sharp renormalized resonance mode at zero frequency and a broad mid-infrared excitation band. Detailed analysis reveals a moderate enhancement of the effective mass at low temperature and low frequency.

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N. L. Wang, J. J. McGuire, T. Timusk, R. Jin, J. He, D Mandrus. 2002-06-07. Optical evidence for mass enhancement of quasiparticles in pyrochlore Cd$_2$Re$_2$O$_7$. https://doi.org/10.1103/physrevb.66.014534

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