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تسجيل مستخدم جديدThermally Driven Josephson Oscillations in Superfluid 4He
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We find that a temperature differential can drive superfluid oscillations in 4He. The oscillations are excited by a heater which causes a time dependent temperature differential across an array of 70nm apertures. By measuring the oscillation frequency and simultaneously determining both temperature and pressure differentials we prove the validity of the most general form of the Josephson frequency relation. These observations were made near saturated vapor pressure, within a few mK of the superfluid transition temperature.
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Fundamental considerations predict that macroscopic quantum systems such as superfluids and the electrons in superconductors will exhibit oscillatory motion when pushed through a small constriction. Here we report the observation of these oscillation
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