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arXiv · 0802.3631

Quantum gates and multi-particle entanglement by Rydberg excitation blockade and adiabatic passage

Ditte Moller·Lars Bojer Madsen·Klaus Molmer
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Abstract

We propose to apply stimulated adiabatic passage to transfer atoms from their ground state into Rydberg excited states. Atoms a few micrometers apart experience a dipole-dipole interaction among Rydberg states that is strong enough to shift the atomic resonance and inhibit excitation of more than a single atom. We show that the adiabatic passage in the presence of this interaction between two atoms leads to robust creation of maximally entangled states and to two-bit quantum gates. For many atoms, the excitation blockade leads to an effective implementation of collective-spin and Jaynes-Cummings-like Hamiltonians, and we show that the adiabatic passage can be used to generate collective Jx=0 eigenstates and Greenberger-Horne-Zeilinger states of tens of atoms.

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Ditte Moller, Lars Bojer Madsen, Klaus Molmer. 2008-02-25. Quantum gates and multi-particle entanglement by Rydberg excitation blockade and adiabatic passage. https://doi.org/10.1103/physrevlett.100.170504

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