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arXiv · 0907.2245

Many-body treatment of the collisional frequency shift in fermionic atoms

A. M. Rey·A. V. Gorshkov·C. Rubbo
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Abstract

Recent clock experiments have measured density-dependent frequency shifts in polarized fermionic alkaline-earth atoms using 1S0-3P0 Rabi spectroscopy. Here we provide a first-principles non-equilibrium theoretical description of the interaction frequency shifts starting from the microscopic many-body Hamiltonian. Our formalism describes the dependence of the frequency shift on excitation inhomogeneity, interactions, and many-body dynamics, provides a fundamental understanding of the effects of the measurement process, and explains the observed density shift data. We also propose a method to measure the second of the two 1S0-3P0 scattering lengths, whose knowledge is essential for quantum information processing and quantum simulation applications.

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A. M. Rey, A. V. Gorshkov, C. Rubbo. 2009-08-26. Many-body treatment of the collisional frequency shift in fermionic atoms. https://doi.org/10.1103/physrevlett.103.260402

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