Ensemble qubits with strong coupling to photons and resilience against
single atom loss are promising candidates for building quantum networks. We report
on progress towards high fidelity preparation and control of ensemble qubits using
Rydberg blockade. Our previous demonstration of ensemble qubit preparation at
a fidelity <60% was possibly limited by Rydberg blockade leakage due to uncontrolled
short range atom pair separation. We show progress towards ensembles with
a blue-detuned 1-D lattice on top of the existing red-detuned dipole trap, which
will suppress unwanted Rydberg interactions by imposing constraints on the atomic
separation. We study the effect of lattice insertion on the fidelity of ensemble state
preparation and Rydberg-mediated gates. Studies of cooperative scattering from a
1D atomic array will also be presented.
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Photon-photon interactions in Rydberg-atom arrays
We investigate the interaction of weak light fields with two-dimensional lattices of atoms with high lying atomic Rydberg states. This system features different interactions that act on disparate length scales, from zero-range defect scattering of atomic excitations and finite-range dipole exchange processes to long-range Rydberg-state interactions, which span the entire array and can block multiple Rydberg excitations. Analyzing their interplay, we identify conditions that yield a nonlinear quantum mirror which coherently splits incident fields into correlated photon-pairs in a single transverse mode, while transmitting single photons unaffected. In particular, we find strong anti-bunching of the transmitted light with equal-time pair correlations that decrease exponentially with an increasing range of the Rydberg blockade. Such strong photon-photon interactions in the absence of photon losses open up promising avenues for the generation and manipulation of quantum light, and the exploration of many-body phenomena with interacting photons.
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- Award ID(s):
- 2116679
- PAR ID:
- 10334125
- Date Published:
- Journal Name:
- Quantum
- Volume:
- 6
- ISSN:
- 2521-327X
- Page Range / eLocation ID:
- 674
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.22331/q-2022-03-30-674
