We calculate the current-pressure relation for pinholes connecting twovolumes of bulk superfluid 3He-B. The theory of multiple Andreev reflections,adapted from superconducting weak links, leads to a nonlinear dependence of thedc current on pressure bias. In arrays of pinholes one has to take into accountoscillations of the texture at the Josephson frequency. The associatedradiation of spin waves from the junction leads to an additional dissipativecurrent at small biases, in quantitative agreement with measurements.
展开▼
