Photonic integrated circuits are an important next-wave technology. These sophisticated microchips hold the potential to substantially decrease costs and increase speed and efficiency for electronic devices across a wide range of application areas, including automotive technology, communications, health care, data storage, and computing for artificial intelligence.
Photonic circuits use photons, fundamental particles of light, to move, store, and access information in much the same way that conventional electronic circuits use electrons for this purpose. Photonic chips are already in use today in advanced fiber-optic communication systems, and they are being developed for implementation in a broad spectrum of near-future technologies, including light detection and ranging, or LiDAR, for autonomous vehicles; light-based sensors for medical devices; 5G and 6G communication networks; and optical and quantum computing.
Given the broad range of existing and future uses for photonic integrated circuits, access to equipment that can fabricate chip designs for study, research and industrial applications is also important. However, today’s nanofabrication facilities cost millions of dollars to construct and are well beyond the reach of many colleges, universities, and research labs.
For those who can access a nanofabrication facility, at least a day must be reserved for the exacting and time-consuming lithographic process used to make these microchips. On top of that, if an error is made in design, or if the chip doesn’t work properly for some other reason, the faulty circuit must be discarded, the design adjusted, and a new chip fabricated. This often results in days or even weeks spent in the cleanroom.
But now, as described in a new paper in Science Advances, a University of Washington-led research team has devised a way to bypass expensive nanofabrication facilities and produce photonic integrated circuits almost anywhere.
The team has developed an innovative method in which these circuits can be written, erased, and modified by a laser writer into a thin film of phase-change material similar to what is used for recordable CDs and DVDs. This new process allows photonic integrated circuits to be constructed and reconfigured in a fraction of the time it would take at a nanofabrication lab.
The multi-university team was led by UW Electrical and Computer Engineering and Physics Professor Mo Li, who is the Department’s associate chair for research, a member of the Institute for Nano-Engineered Systems and the senior author of the paper.
“Photonics technology is on the horizon; therefore, we need to train or educate our students in this field. But for students to study and have hands-on experience with photonic circuits, currently, they need access to a multimillion-dollar facility,” Li said.
“This new technology addresses that problem. Using our method, photonic circuits that previously had to be fabricated in expensive and hard-to-access facilities now can be printed and reconfigured in labs, classrooms, and even garage workshops, by a speedy, low-cost device about the size of a conventional desktop laser printer.”
Benefits for students, researchers and industry
Students aren’t the only ones who stand to benefit from this new way of creating photonic integrated circuits. For researchers, this advance will enable a much quicker turnaround time for prototyping and testing out a new idea before booking valuable time in a nanofabrication facility.
Source: University of Washington