Optical evidence for mass enhancement of quasiparticles in pyrochlore Cd₂Re₂O₇

الأصل · EN

We report on the results of optical studies of the newly discovered superconductor Cd₂Re₂O₇ 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.