Raman spectroscopy of the charge-Density-Wave state in TaS3

Raman spectroscopy has been used to study the quasi-one-dimensional charge-density-wave (CDW) compound, TaS3. We determine for the first time both the temperature dependence of the CDW order parameter and the magnitude of the electronic gap 2Δ(T) opened by the CDW at the Fermi surface. The transition to the CDW state appears to be continuous; our value of 2Δ(0)530 cm-1 is in agreement with both theory and transport measurements. © 1978 The American Physical Society.