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Collective molecule formation in a degenerate Fermi gas via a Feshbach resonance

Juha Javanainen·Marijan Kostrun·Yi Zheng·Andrew Carmichael·Uttam Shrestha·Patrick J. Meinel·Matt Mackie·Olavi Dannenberg·Kalle-Antti Suominen
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Abstract

We model collisionless collective conversion of a degenerate Fermi gas into bosonic molecules via a Feshbach resonance, treating the bosonic molecules as a classical field and seeding the pairing amplitudes with random phases. A dynamical instability of the Fermi sea against association into molecules initiates the conversion. The model qualitatively reproduces several experimental observations {[Regal et al., Nature {\bf 424}, 47 (2003)]}. We predict that the initial temperature of the Fermi gas sets the limit for the efficiency of atom-molecule conversion.

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Juha Javanainen, Marijan Kostrun, Yi Zheng, Andrew Carmichael, Uttam Shrestha, Patrick J. Meinel, Matt Mackie, Olavi Dannenberg, Kalle-Antti Suominen. 2004-06-16. Collective molecule formation in a degenerate Fermi gas via a Feshbach resonance. https://doi.org/10.1103/physrevlett.92.200402

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