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arXiv · 2207.01270

Tomography of a number-resolving detector by reconstruction of an atomic many-body quantum state

Mareike Hetzel·Luca Pezzè·Cebrail Pür·Martin Quensen·Andreas Hüper·Jiao Geng·Jens Kruse·Luis Santos·Wolfgang Ertmer·Augusto Smerzi·Carsten Klempt
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Abstract

The high-fidelity analysis of many-body quantum states of indistinguishable atoms requires the accurate counting of atoms. Here we report the tomographic reconstruction of an atom-number-resolving detector. The tomography is performed with an ultracold rubidium ensemble that is prepared in a coherent spin state by driving a Rabi coupling between the two hyperfine clock levels. The coupling is followed by counting the occupation number in one level. We characterize the fidelity of our detector and show that a negative-valued Wigner function is associated with it. Our results offer an exciting perspective for the high-fidelity reconstruction of entangled states and can be applied for a future demonstration of Heisenberg-limited atom interferometry.

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Mareike Hetzel, Luca Pezzè, Cebrail Pür, Martin Quensen, Andreas Hüper, Jiao Geng, Jens Kruse, Luis Santos, Wolfgang Ertmer, Augusto Smerzi, Carsten Klempt. 2022-07-04. Tomography of a number-resolving detector by reconstruction of an atomic many-body quantum state. https://arxiv.org/abs/2207.01270

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