Abstract
We describe the operation of a hydromechanical resonator immersed in and superfluids and opened on the main bath by two holes, a micro-orifice acting as a weak link and a long parallel channel. Transitions between adjacent quantum states differing by one hydrodynamic circulation quantum can be induced coherently, yielding a succession of steps arranged in a staircase pattern. In at about 0.8 mK and 0 bar, a nearly ideal, nondissipative hydrodynamic Josephson effect can be observed.
- Received 24 August 1987
DOI:https://doi.org/10.1103/PhysRevLett.60.416
©1988 American Physical Society