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arXiv · 2006.03071

Entangling logical qubits with lattice surgery

Alexander Erhard·Hendrik Poulsen Nautrup·Michael Meth·Lukas Postler·Roman Stricker·Martin Ringbauer·Philipp Schindler·Hans J. Briegel·Rainer Blatt·Nicolai Friis·Thomas Monz
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Abstract

Future quantum computers will require quantum error correction for faithful operation. The correction capabilities come with an overhead for performing fault-tolerant logical operations on the encoded qubits. One of the most resource efficient ways to implement logical operations is lattice surgery, where groups of physical qubits, arranged on lattices, can be merged and split to realize entangling gates and teleport logical information. Here, we report on the experimental realization of lattice surgery between two topologically encoded qubits in a 10-qubit ion trap quantum information processor. In particular, we demonstrate entanglement between two logical qubits and we implement logical state teleportation.

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Alexander Erhard, Hendrik Poulsen Nautrup, Michael Meth, Lukas Postler, Roman Stricker, Martin Ringbauer, Philipp Schindler, Hans J. Briegel, Rainer Blatt, Nicolai Friis, Thomas Monz. 2020-06-04. Entangling logical qubits with lattice surgery. https://doi.org/10.1038/s41586-020-03079-6

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