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arXiv · 1709.02318

Lattice Surgery with a Twist: Simplifying Clifford Gates of Surface Codes

Daniel Litinski·Felix von Oppen
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Abstract

We present a planar surface-code-based scheme for fault-tolerant quantum computation which eliminates the time overhead of single-qubit Clifford gates, and implements long-range multi-target CNOT gates with a time overhead that scales only logarithmically with the control-target separation. This is done by replacing hardware operations for single-qubit Clifford gates with a classical tracking protocol. Inter-qubit communication is added via a modified lattice surgery protocol that employs twist defects of the surface code. The long-range multi-target CNOT gates facilitate magic state distillation, which renders our scheme fault-tolerant and universal.

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Daniel Litinski, Felix von Oppen. 2017-09-07. Lattice Surgery with a Twist: Simplifying Clifford Gates of Surface Codes. https://doi.org/10.22331/q-2018-05-04-62

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