The non-Ohmic transport properties of NbSe3 are studied near the two phase transitions at T1 and T2. From the non-Ohmic data a parameter ± is obtained which provides information on the fraction of Fermi surface affected by the phase transitions. By relating ± to a BCS-type gap and modifying the calculations of Fedders and Martin on the spin-density-wave state in Cr we have obtained a theoretical curve for ± which agrees well with the experimental data. This good agreement provides new indirect evidence for the charge-density-wave (CDW) state in NbSe3. The derivative of the low-field resistivity versus temperature has also been measured and is shown to be divergent at T1 and T2. The index of this divergence is presented and its significance to the dimensionality of the system is discussed. Finally, we briefly discuss the possibility of explaining the non-Ohmicity below T1 in terms of nonlinear excitations in a CDW condensate.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics