2014/10/28 by Ying Li · 1 voice · 3 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1088/1367-2630/17/2/023037
published as New J. Phys. 17, 023037 (2015) · 5 pages, 4 figures
arxiv created 2014/10/28 · arxiv updated 2015/03/24
The leading approach to fault tolerant quantum computing requires a continual supply of magic states. When a new magic state is first encoded, its initial fidelity will be too poor for use in the computation. This necessitates a resource-intensive distillation process that occupies the majority of the computer's hardware; creating magic states with a high initial fidelity minimises this cost and is therefore crucial for practical quantum computing. Here we present the surprising and encouraging result that raw magic states can have a fidelity significantly better than that of the two-qubit gate operations used to construct them. Our protocol exploits post-selection without significantly slowing the rate of generation and tolerates finite error rates in initialisations, measurements and single-qubit gates. This approach may dramatically reduce the size of the hardware needed for a given quantum computing task.