Fault-tolerant quantum computation

TL;DR

This paper discusses how quantum error correction enables fault-tolerant quantum computing by protecting information from errors, allowing reliable long-term quantum computations if error rates are below a critical threshold.

Contribution

It reviews the principles of quantum error correction and introduces the concept of fault-tolerant quantum computation, highlighting the potential for intrinsic fault tolerance in hardware design.

Findings

Quantum error correction significantly improves quantum computing prospects.

Fault-tolerance can be achieved if error rates are below a certain threshold.

Topological interactions may enable intrinsic fault-tolerant hardware.

Abstract

The discovery of quantum error correction has greatly improved the long-term prospects for quantum computing technology. Encoded quantum information can be protected from errors that arise due to uncontrolled interactions with the environment, or due to imperfect implementations of quantum logical operations. Recovery from errors can work effectively even if occasional mistakes occur during the recovery procedure. Furthermore, encoded quantum information can be processed without serious propagation of errors. In principle, an arbitrarily long quantum computation can be performed reliably, provided that the average probability of error per gate is less than a certain critical value, the accuracy threshold. It may be possible to incorporate intrinsic fault tolerance into the design of quantum computing hardware, perhaps by invoking topological Aharonov-Bohm interactions to process quantum information.