Error-free quantum computing gets real
Artist impression of gate operations on logical quantum bits, that are protected from faults by means of quantum error correction. Credit: Johannes Knünz

High-quality fabrication has made errors in processing and storage of information rare in modern computers. For critical applications, where single errors can have serious effects, error correction mechanisms based on redundant data are still used.

Errors will propagate in the system and information will be lost if they are not corrected, because quantum computers are more susceptible to disturbances. Because the laws of quantum mechanics forbid copying quantum information, it is possible to distribute logical quantum information into an entangled state of several physical systems.

A group of physicists led by Thomas Monz of the Department of Experimental Physics at the University of Innsbruck have succeeded for the first time in realizing a set.

A quantum operation has been realized.

The universal gate set was implemented on the ion trap quantum computer. Two quantum bits were distributed over seven atoms.

For the first time, it has been possible to implement two computational gates on fault tolerant quantum bits, which are necessary for a universal set of gates.

T gates are very fundamental operations, and they are particularly interesting because they are easy to use on classical computers. This is no longer possible with T gates, as demonstrated by the physicists.

Error-free quantum computing gets real
Fundamental building blocks for fault-tolerant quantum computing demonstrated. Credit: Uni Innsbruck/Harald Ritsch

Accuracy also increases.

The stored quantum information is protected from errors. Computational operations are error-prone and this is useless without them.

Errors caused by the underlying physical operations can be detected and corrected by the researchers. They implemented the first fault tolerant implementation of a universal set of gates.

The implementation of fault-tolerant requires more operations than non-fault-tolerant operations. The experimental operations on the logical qubits are better than non-fault- tolerant logical operations, despite the fact that this will introduce more errors on the scale of single atoms.

Physicists have demonstrated all the building blocks for a quantum computer. The task is to implement these methods on larger quantum computers. Other architectures for quantum computers can be used with the methods shown in Innsbruck.

Nature published the research.

More information: Philipp Schindler et al, Demonstration of fault-tolerant universal quantum gate operations, Nature (2022). DOI: 10.1038/s41586-022-04721-1. Journal information: Nature Citation: Error-free quantum computing gets real (2022, May 25) retrieved 25 May 2022 from This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.