Magic-state distillation with the four-qubit code

TL;DR

This paper introduces a new magic-state distillation routine using a four-qubit error-detecting code, significantly reducing overhead for practical quantum computing applications.

Contribution

It presents a novel distillation method that lowers resource requirements by combining a four-qubit code with existing routines, enhancing efficiency in quantum error correction.

Findings

Reduces the number of input states needed per output

Combines with Bravyi-Kitaev routine for further overhead reduction

Improves practicality of universal quantum computing

Abstract

The distillation of magic states is an often-cited technique for enabling universal quantum computing once the error probability for a special subset of gates has been made negligible by other means. We present a routine for magic-state distillation that reduces the required overhead for a range of parameters of practical interest. Each iteration of the routine uses a four-qubit error-detecting code to distill the +1 eigenstate of the Hadamard gate at a cost of ten input states per two improved output states. Use of this routine in combination with the 15-to-1 distillation routine described by Bravyi and Kitaev allows for further improvements in overhead.