Pairing gap and in-gap excitations in trapped fermionic superfluids

J. Kinnunen; M. Rodriguez; P. Torma

doi:10.1126/science.1100782

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Pairing gap and in-gap excitations in trapped fermionic superfluids

J. Kinnunen·M. Rodriguez·P. Torma

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Abstract

We consider trapped atomic Fermi gases with Feshbach-resonance enhanced interactions in pseudogap and superfluid temperatures. We calculate the spectrum of RF(or laser)-excitations for transitions that transfer atoms out of the superfluid state. The spectrum displays the pairing gap and also the contribution of unpaired atoms, i.e. in-gap excitations. The results support the conclusion that a superfluid, where pairing is a many-body effect, was observed in recent experiments on RF spectroscopy of the pairing gap.

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cond-mat.supr-con cond-mat.mes-hall cond-mat.stat-mech cond-mat.str-el quant-ph

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J. Kinnunen, M. Rodriguez, P. Torma. 2004-07-26. Pairing gap and in-gap excitations in trapped fermionic superfluids. https://doi.org/10.1126/science.1100782

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