A complete platform for quantum computing

DTU researchers strengthen their grip on the quantum computer

Credit: Technical University of Denmark

In groundbreaking new work, DTU researchers have now achieved the complete platform for an optical quantum computer. The platform is universal and scalable, everything takes place at room temperature, and the technology is directly compatible with standard fiber optic networks. This places DTU at the forefront of development.

Optical quantum computers have long been eclipsed by superconducting technologies which have been accelerated by huge development programs executed by tech giants like IBM and Google. The situation is now changing, in particular thanks to a series of pioneering projects carried out by researchers from the bigQ fundamental research center of the DTU Physique.

In fact, DTU researchers are not limited to simply developing individual components for an optical quantum computer or simply a quantum simulator. They are working with determination on the development of a universal optical quantum computer based on measurement.

Can execute any arbitrary algorithm

Although the type of quantum computer that DTU researchers are developing is conceptually very different from a normal computer, there are similarities as well.

There are basic logical devices (qubits) that carry information, and there are gates that perform operations on one or more qubits, thus implementing an algorithm.

The demonstration of a so-called universal set of gates – and the implementation of a number of operations using it – is precisely what constitutes the new advance in optical quantum computing.

“Our demonstration of a universal set of doors is absolutely critical. This means that any arbitrary algorithm can be performed on our platform with the right inputs, namely optical qubits. The computer is fully programmable, ”says Mikkel Vilsbøll Larsen, who was the main driving force behind the work and who recently completed his doctorate. studies at the DTU.

Scaling makes the quantum computer practically relevant

The potential of the quantum computer is enormous, and its significantly increased processing power compared to standard solid-state computers will enable breakthrough innovation in a wide range of areas of great importance to Denmark, such as the pharmaceutical industry. , optimization of the transport sector, and the development of materials for carbon capture and storage.

A crucial factor in realizing this potential is that the quantum computer is realized on a platform scalable to thousands of qubits, says lead researcher Jonas S. Neergaard-Nielsen, who is one of the pillars of the work.

“Theoretically, there is no difference between whether a quantum computer is based on superconducting or optical qubits. But there is a decisive practical difference. Superconducting quantum computers are limited to the number of qubits made on the machine. specific processor chip. In our system, we are constantly creating new ones and quantum entangling them with those we are performing calculations on. This means that our platform is easily scalable. “

“Plus, we don’t need to cool everything in large cryostats. Instead, we can do it all at room temperature in fiber optics. The fact that the system is based on optical fibers also means that it can be connected directly to a future quantum internet, without difficult intermediaries. “

Researchers have already taken the step to scale in 2019 when, in an article by Science– they explained how, among the first in the world, they produced the basic structure of a measurement-based optical quantum computer – a so-called two-dimensional cluster state with over 30,000 entangled light states.

Already looking to the future with determination

Although they may be tempted to rest on their laurels for a moment, the research team already has new goals in sight.

Earlier this year, they developed and patented a comprehensive theoretical framework explaining how their technology can incorporate long-term error correction as well. This is one of the great challenges facing quantum computing today.

“This is an important research result that we have just published, and we are proud of it. But our ambitions go far beyond that. The long term goal is a quantum computer who can solve relevant problems and realize the potential towards which we are all striving, ”says Prof. Ulrik L. Andersen, who leads bigQ and oversaw the entire research program.

“We know what it takes to put our current technology on an optical chip and introduce correction of errors, and we have set up the relevant international collaborations. The same goes for the enterprise sector, where companies are keen to develop use cases with us. “

In other words, DTU researchers are ready to take up the next challenges and take the step from basic research to innovation. In fact, funding is the only thing missing.

The research was published in the journal Physics of nature.


Advances in algorithms make noisy small quantum computers viable


More information:
Mikkel V. Larsen et al, Deterministic multimode gates on an evolutionary photonic quantum computing platform, Physics of nature (2021). DOI: 10.1038 / s41567-021-01296-y

Mikkel V. Larsen et al, Deterministic generation of a two-dimensional cluster state, Science (2019). DOI: 10.1126 / science.aay4354

Quote: A Complete Platform for Quantum Computing (2021, August 13) retrieved August 13, 2021 from https://phys.org/news/2021-08-platform-quantum.html

This document is subject to copyright. Other than fair use for private study or research purposes, no part may be reproduced without written permission. The content is provided for information only.

Leave a Reply

Your email address will not be published. Required fields are marked *