3He Josephson Junctions
نویسندگان
چکیده
The flow of superfluid 3He-B through a 65 3 65 array of nanometer-size apertures has been measured recently by Backhaus et al. They find in the current-phase relation a new branch, the so-called p state. We study two limiting cases which show that the p state arises from the coupling of the phase degree of freedom to the spin-orbit rotation. The p state exists in a single large aperture, but is difficult to observe because of hysteresis. A better correspondence with experiments is obtained by assuming a thin wall, where the Josephson coupling between the two sides arises from a dense array of pinholes.
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