engleski

Doping effects on the low-energy excitations of the charge density wave system o-TaS3

We report on the effect of doping on the relaxational dynamics and the specific heat (Cp) of the charge density wave (CDW) system o-TaS3. Isoelectronic substitution of Ta atoms with 0.2%-0.5% of Nb suppresses the primary relaxation process responsible for the glass-like dielectric response of pure o-TaS3 but only slightly affects the secondary process as well as the low energy excitation (LEE) contribution to Cp. Our results show that the primary relaxation process is mainly due to long range deformations of the CDW, which are prevented by doping. The secondary process and the LEE contribution to Cp originate from local topological defects of the CDW still remaining in doped samples.

charge density wave ; heat capacity ; dielectric response ; relaxations ; doping

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