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arXiv · 1301.4079

Coherent state of a weakly interacting ultracold Fermi gas

Arnab Ghosh·Sudarson Sekhar Sinha·Deb Shankar Ray
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Abstract

We examine the weakly interacting atoms in an ultracold Fermi gas leading to a state of macroscopic coherence, from a theoretical perspective. It has been shown that this state can be described as a fermionic coherent state. These coherent states are the eigenstates of fermionic annihilation operators, the eigenvalues being anti-commuting numbers or Grassmann numbers. By exploiting the simple rules of Grassmann algebra and a close kinship between relations evaluated for more familiar bosonic fields and those for fermionic fields, we derive the thermodynamic limit, the spontaneous symmetry breaking and the quasi-particle spectrum of the fermionic system.

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Arnab Ghosh, Sudarson Sekhar Sinha, Deb Shankar Ray. 2013-01-17. Coherent state of a weakly interacting ultracold Fermi gas. https://arxiv.org/abs/1301.4079

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