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arXiv · 0805.0440

Scaling the neutral atom Rydberg gate quantum computer by collective encoding in Holmium atoms

M. Saffman·K. Molmer
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Abstract

We discuss a method for scaling a neutral atom Rydberg gate quantum processor to a large number of qubits. Limits are derived showing that the number of qubits that can be directly connected by entangling gates with errors at the $10^{-3}$ level using long range Rydberg interactions between sites in an optical lattice, without mechanical motion or swap chains, is about 500 in two dimensions and 7500 in three dimensions. A scaling factor of 60 at a smaller number of sites can be obtained using collective register encoding in the hyperfine ground states of the rare earth atom Holmium. We present a detailed analysis of operation of the 60 qubit register in Holmium. Combining a lattice of multi-qubit ensembles with collective encoding results in a feasible design for a 1000 qubit fully connected quantum processor.

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M. Saffman, K. Molmer. 2008-05-04. Scaling the neutral atom Rydberg gate quantum computer by collective encoding in Holmium atoms. https://doi.org/10.1103/physreva.78.012336

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