FURTHER EXPERIMENTS ON NARROW-BAND CONDUCTION NOISE IN NBSE3

Further measurements of the conduction noise associated with motion of the higher temperature charge-density wave in NbSe3 are reported. The individual harmonic amplitudes fluctuate randomly and independently. The spectral width is fully represented on timescales of 10 ms or less . The Gaussian nature of the noise is employed to make reproducible me asurements of the bias dependence of the total noise amplitude (summed over harmonics), which increases with increasing bias above threshold , then saturates when its fundamental frequency exceeds f(k). The magn itude of the saturation noise voltage varies with temperature in the m anner of an order parameter, while f(k) largely mimics the threshold f ield. The harmonic content is roughly independent of bias and temperat ure.