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Optical investigation of the charge-density-wave phase transitions in $NbSe_{3}$

A. Perucchi·L. Degiorgi·R. E. Thorne
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Abstract

We have measured the optical reflectivity $R(ω)$ of the quasi one-dimensional conductor $NbSe_{3}$ from the far infrared up to the ultraviolet between 10 and 300 $K$ using light polarized along and normal to the chain axis. We find a depletion of the optical conductivity with decreasing temperature for both polarizations in the mid to far-infrared region. This leads to a redistribution of spectral weight from low to high energies due to partial gapping of the Fermi surface below the charge-density-wave transitions at 145 K and 59 K. We deduce the bulk magnitudes of the CDW gaps and discuss the scattering of ungapped free charge carriers and the role of fluctuations effects.

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A. Perucchi, L. Degiorgi, R. E. Thorne. 2003-10-30. Optical investigation of the charge-density-wave phase transitions in $NbSe_{3}$. https://doi.org/10.1103/physrevb.69.195114

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