Laser chips

Collaborations could pave the way for new laser-on-chip applications

Lasers and silicon chips could be ranked among the top two innovations of the modern world.

Silicon chips, invented in 1958, are in everything from computers and phones to cars and spaceships. Lasers, invented in 1960, are being used in everything from laser eye surgery, laser printers, LiDAR in self driving cars, remote sensing of landscapes and numerous medical, scientific and military devices.

But now we are at the beginning of a new technological revolution that marries these two great inventions.

Lukas Chrostowski, an electrical and computer engineering professor at the University of British Columbia and co-founder of a startup, Dream Photonics, wants to integrate lasers on chips that are inexpensive enough for a wide array of applications.

“We came up with a way that we think could get the cost down to about two dollars a laser,” Chrostowski says. “We want to commercialize sensors and lasers together and address the integration challenge of putting lasers on silicon photonic chips.”

To do that Chrostowski is leveraging the facilities at the University of British Columbia, which is part of the Quantum Colaboratory (Quantum Colab) research and development environment that brings quantum technology to life.

Quantum Colab involves Institut Quantique at the Université de Sherbrooke, the Stewart Blusson Quantum Matter Institute at the University of British Columbia and the Transformative Quantum Technologies (TQT) technology vector research initiative of the Institute for Quantum Computing at the University of Waterloo.

Although lasers are being put on silicon chips today, by companies such as Intel and Cisco, they are not yet cost effective enough and available for smaller companies to utilize them for an array of different applications, Chrostowski explains.

“I’ve been dreaming of the day when I can drag and drop a laser into an integrated circuit layout using computer aided design software. The laser would sit alongside waveguides, splitters, detectors, modulators, and some exotic components. Then I would submit my design to a foundry, and receive a laser-integrated silicon chip,” he says in a recent article he wrote for LinkedIn.

The work has its origins in the Silicon Electronics-Photonics Integrated Circuits Fabrication (SiEPICfab) consortium that brought together 17 companies and six universities to provide research and fabrication capabilities, and accelerate the development of silicon photonics. It has also had funding support through the Refined Manufacturing Acceleration Process (REMAP) network supported by the federal government’s Networks of Centres of Excellence program.

Chrostowski says if lasers on chips could be used in low-cost sensor devices, that would significantly reduce the cost of manufacturing technologies such as smartwatches that detect the biomarkers for various diseases or rapid Covid-19 and other virus testing systems.

It would also create enormous potential for cost reductions and new developments in everything from the next generation of LiDAR in self driving cars to the development of quantum computers.

Moreover, it would facilitate future quantum computing, Chrostowski adds.  

A number of companies are already working on photonic-based quantum computing.  

“Each of those optical quantum computing companies will need lasers in order to generate single photons or squeezed photons. They need quantum states of light,” he says. “Then, for quantum communication, you also need lasers to generate single photons, which are then used for transmission of information.”

Collaboration is the key to what Dream Photonics is trying to do.

Chrostowski says the use of the Quantum Colab facilities at UBC is critical to the work, along with the expertise provided by other academic and industry partners.

“Dream Photonics is contributing to the laser integration, but there are other people who are contributing to the manufacturing steps along the way,” Chrostowski says.

The company is not a traditional startup with venture capital funding, but rather, part of an international academic and industry effort to enable companies access to a whole suite of different applications for lasers on chip, he says.

“We want to help other people with their applications by developing a process and sharing it, and by developing tools and libraries of devices that connect to the laser,” Chrostowski says. “The idea is that there could be 50 different products, but there are a lot of commonalities, so what we want is a common manufacturing pipeline.”

By collaborating with industry and university partners, Chrostowski says he gets access to knowledge, people and equipment that might not be available to a small company such as Dream Photonics.

From the point of view of the universities and the government, these collaborations help to get innovations out of the lab and into the commercial space, which helps the economy and provides a return on their investments.

“Dream Photonics benefits from the use of the UBC facilities, processes and the expertise of people who are highly qualified and trained. We rely on newly trained people who are coming out, and who help feed the company,” Chrostowski says.

With rapid progress in this field, Chrostowski believes 2022 will be a “pivotal year” for laser-enabled chips.

“There will be a flurry of opportunities in terms of new products and new ideas. If people can build small systems instead of having big boxes for the laser and if you can put a whole bunch of lasers on a chip, new things will come out of it,” he says.

For Chrostowski, seeing new applications for lasers on chips is the culmination of a lifetime of fascination with lasers.

His father, who worked for the National Research Council, introduced him to lasers when he was a child, and he also saw them in the Star Wars movies. It was natural for him to want to study lasers and take them to the next stage. “Every time I had to make a choice about what to do next, somehow, lasers were there,” he says.

Now that lasers on chips are a reality, he is excited and eager to the new possibilities and potential being unlocked.

“Lasers have been around for my whole life but they have been big and bulky. The transition I am seeing today is that lasers are small and now being integrated on chips. The question is, what will this open up in the future?” Chrostowski says.

“I think it can unlock possibilities in terms of imagination, creativity, innovation by many people, not just me. I’m excited to see what people will come up with in terms of applications.”