Bloch and Josephson Oscillations in a Ring of an Ideal Bose Gas

Leon Gunther

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arXiv · 1002.1283

Bloch and Josephson Oscillations in a Ring of an Ideal Bose Gas

Leon Gunther

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Abstract

We show that an Ideal Bose gas that is contained within a very thin ring exhibits phenomena analogous to the Bloch and Josephson oscillations of a charged Ideal Fermi gas in a thin ring. If the walls of the ring are constrained to have an angular velocity $ω$, the angular momentum has an anomalous component that is periodic in $ω$, with a period equal to the quantum of angular velocity $ω_{0}\equiv \hbar /mR^{2}$. If a constant applied torque is applied to the walls, there will be component of the angular momentum of the gas that is periodic in time, with a 'Josephson frequency' given by $f_{J} =τ/N \hbar$. Finally, we show that the oscillations are an automatic feature of the quantum regime of any ring of an ensemble of identical particles, even with particle interactions.

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Leon Gunther. 2010-02-05. Bloch and Josephson Oscillations in a Ring of an Ideal Bose Gas. https://arxiv.org/abs/1002.1283

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