Measurement of Turbulence in Superfluid 3 He - B
نویسندگان
چکیده
The experimental investigation of superfluid turbulence in 3 He-B is generally not possible with the techniques which have been developed for 4 He-II. We describe a new method by which a transient burst of turbulent vortex expansion can be generated in 3 He-B. It is based on the injection of a few vortex loops into rotating vortex-free flow. The time-dependent evolution of the quantized vorticity is then monitored with NMR spectroscopy. Using these techniques the transition between regular (i.e. vortex number conserving) and turbulent vortex dynamics can be recorded at T ∼ 0.6 T c and a number of other characteristics of turbulence can be followed down to a temperature of T 0.4 T c .
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