Photonic Quantum Computer: Computing with Light

Femtosecond Laser Processing of Integrated Quantum Optical Chips (FLMOptChips)

Researchers from the MATERIALS Institute at JOANNEUM RESEARCH were recently approved a 1.3 million euro quantum technology project. The aim is to develop optical chips for a photonic quantum computer that enables direct quantum computing with photons. Physicist Bernhard Lamprecht is project leader of FLMOptChips at the institute’s site in Weiz, Austria. The production of these optical chips takes place exclusively there.

In the FLMOptChips project, light is used directly for computing. Project leader Bernhard Lamprecht explains: “We are working on an optical quantum computer as part of this project. The quantum bit, or qubit, as the basic unit of a quantum computer, is realised here with light particles, so-called photons. For quantum computing with photons, special reconfigurable optical chips are needed.” The development of these chips is at the centre of the new project of the MATERIALS Institute: “The goal is to use ultrashort-pulse laser lithography to write optics such as optical waveguides and other required optoelectronical components into sub-mm-thin glass substrates, about the size of a credit card. These customised miniaturised optical structures with high resolution in the micrometre range are the basic hardware for this type of quantum computer,” the physicist continues.

In the FLMOptChips project, the MATERIALS Institute develops the necessary optics and optoelectronics for the photonic quantum computer and manufactures the corresponding photonic quantum chips. A team of researchers from the Light and Optical Technologies research group is working on this since October 2022.

A quantum computer uses the laws of quantum mechanics. The smallest information carrier in the computing process is the qubit. “There are at least ten different ways to realise qubits. The realisation through electronic excitation states in atoms trapped in ion traps, as we are doing together with the University of Innsbruck and Infineon in the joint OptoQuant project, is one possibility. A realisation with photons propagating in special photonic chips, as in the new project, is another possibility. What will ultimately catch on is completely open now. What is certain, however, is that in both cases you need light, and thus integrated optics. This is particularly interesting for us, as it coincides with one of our core competencies at the institute.”

The Austrian FFG research funding initiative Quantum Austria is funding FLMOptChips, which essentially supports innovative research in the field of quantum physics, such as quantum computing. There is an internationally relevant research community in Austria to advance quantum research with regard to marketable quantum computers. “The methods developed in the joint OptoQuant project, in particular for the production of integrated waveguides, serve as the basis and starting point for the new FLMOptChips project and will be taken up and further developed in this. This technology is new in Austria. Through these developments we are bringing new added value to the country,” Lamprecht adds.

Professor Philip Walther, from the University of Vienna, will carry out the first test of the new optical chips. He is head of the Quantum Computation and Quantum Information Science group there. In his research and publication work, he described the requirements for optical chips. Therefore, he will test the quality of the photonic chips fabricated by JOANNEUM RESEARCH in his quantum optics laboratories in Vienna.

The project:

Femtosecond Laser Processing of Integrated Quantum Optical Chips (FLMOptChips).
FFG Quantum Austria – 1st call for proposals
Eligible costs: 1.231.333 €
Start: 1.10.2022 / End: 30.9.2025

Enquiry reference:

Dr Bernhard Lamprecht
MATERIALS – Light and Optical Technologies
Phone: +43 316 876-3212
bernhard.lamprecht@joanneum.at
Franz-Pichler-Strasse 30, 8160 Weiz, Austria

JOANNEUM RESEARCH Forschungsgesellschaft mbH develops solutions and technologies for business and industry in a broad range of sectors and conducts cutting-edge research at an international level. Well embedded in the national and international innovation network, the researchers develop innovations in the three thematic areas of information and production technologies, human technology and medicine, and society and sustainability.

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