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arXiv · 1811.01939

Momentum-resolved spectroscopy of a 1D superfluid using a single atomic impurity

Francesco Cosco·Massimo Borrelli·Francesco Plastina·Sabrina Maniscalco
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Abstract

We present a general and non-invasive probing scheme to perform full momentum-resolved spectroscopy of a cold atomic gas loaded into an optical lattice using a single quantum impurity. The protocol relies on weak collisional interactions and subsequent population measurements of the impurity. By tuning a few controllable external parameters the impurity-lattice interaction can be engineered, and using two sets of measurements, performed with the impurity in two different positions, the full dispersion relation of the superfluid phonons can be reliably extracted.

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Francesco Cosco, Massimo Borrelli, Francesco Plastina, Sabrina Maniscalco. 2018-11-05. Momentum-resolved spectroscopy of a 1D superfluid using a single atomic impurity. https://arxiv.org/abs/1811.01939

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