Anomalous electronic Raman scattering in NaxCoO2.yH2O.

  title={Anomalous electronic Raman scattering in NaxCoO2.yH2O.},
  author={Peter Lemmens and K Y Choi and Vladimir Gnezdilov and E. Ya. Sherman and D. P. Chen and C. Lin and Fangcheng Chou and Bernhard Keimer},
  journal={Physical review letters},
  volume={96 16},
Raman scattering experiments on NaxCoO2.yH2O single crystals show a broad electronic continuum with a pronounced peak around 100 cm(-1) and a cutoff at approximately 560 cm(-1) over a wide range of doping levels. The electronic Raman spectra in superconducting and nonsuperconducting samples are similar at room temperature, but evolve in markedly different ways with decreasing temperature. For superconducting samples, the low-energy spectral weight is depleted upon cooling below T* approximately… 
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