The Moment of Inertia and the Scissors Mode of a Bose-condensed Gas
نویسندگان
چکیده
We relate the frequency of the scissors mode to the moment of inertia of a trapped Bose gas at finite temperature in a semi-classical approximation. We apply these theoretical results to the data obtained in our previous study of the properties of the scissors mode of a trapped Bose-Einstein condensate of Rb atoms as a function of the temperature. The frequency shifts that we measured show quenching of the moment of inertia of the Bose gas at temperatures below the transition temperature the system has a lower moment of inertia that of a rigid body with the same mass distribution, because of superfluidity. PACS numbers: 03.75.Fi, 05.30.Jp, 32.80.Pj, 67.90.+z
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