Bell correlations in a split two-mode-squeezed Bose-Einstein condensate
- URL: http://arxiv.org/abs/2101.06190v2
- Date: Wed, 24 Nov 2021 18:09:18 GMT
- Title: Bell correlations in a split two-mode-squeezed Bose-Einstein condensate
- Authors: Jonas Kitzinger, Xin Meng, Matteo Fadel, Valentin Ivannikov, Kae
Nemoto, William J. Munro, Tim Byrnes
- Abstract summary: We analyze a protocol for observing a violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality using two spatially separated Bose-Einstein condensates (BECs)
To prepare the Bell-correlated state, spin-changing collisions are used to first prepare a two-mode squeezed BEC.
Spin-changing collisions are also exploited locally, to compensate local squeezing terms.
- Score: 4.5472272129671065
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We propose and analyze a protocol for observing a violation of the
Clauser-Horne-Shimony-Holt (CHSH) Bell inequality using two spatially separated
Bose-Einstein condensates (BECs). To prepare the Bell-correlated state,
spin-changing collisions are used to first prepare a two-mode squeezed BEC.
This is then split into two BECs by controlling the spatial wavefunction, e.g.,
by modifying the trapping potential. Finally, spin-changing collisions are also
exploited locally, to compensate local squeezing terms. The correlators
appearing in the inequality are evaluated using three different approaches. In
the first approach, correlators are estimated using normalized expectation
values of number operators, in a similar way to evaluating continuous-variable
Bell inequalities. An improvement to this approach is developed using the
sign-binning of total spin measurements, which allows for the construction of
two-outcome measurements and violations of the CHSH inequality without
auxiliary assumptions. Finally, we show a third approach where maximal
violations of the CH inequality can be obtained by assigning zero values to
local vacua outcomes under a no-enhancement assumption. The effect of loss and
imperfect detection efficiency is investigated and the observed violations are
found to be robust to noise.
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