NMR Evidence of the Fröhlich Mode inRb0.30MoO3

Current-voltage characteristics, voltage oscillations and NMR on the same Rb0.30MoO3 crystal at 77 K are presented. The 1/2,-1/2; transition at V0=80 MHz of 87Rb nuclei broadened by the CDW modulation is motionally narrowed for bias currents exceeding threshold for non-linear conduction. Calculation of the lineshapes, assuming a partial depinning of the sample, leads to excellent agreement with experiment. An estimate of the ratio of the average current density and voltage oscillation frequency in the depinned region agrees roughly with phenomenological models. A CDW phase correlation time of single domains is deduced to be τ=200 μS.