Shot Noise Acoustic Radiation Generated by Phase Slippage in Superfluid 4He
نویسندگان
چکیده
We present a model calculation and measurements of the acoustic radiation spectrum generated by thermally activated phase slippage driven by a constant pressure head. The calculation of the spectrum, which is similar to that for shot noise in an electrical current, takes into account the stochastic nature of phase-slip vortex nucleation. The observed acoustic amplitude depends on the driving pressure DP, the frequency v, and the quality factor Q of a coupled cavity, as sDPQyv5d1y2, consistent with the model predictions. [S0031-9007(98)06925-7]
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