Scientists at Yale University have created a new type of laser pointer that uses sound waves to amplify light. A study on this finding was published on the online version of the journal Science on June 8.
In recent years, there has been an increasing interest in converting fiber optic technologies, such as fiber optics and free space lasers, into tiny optical or "photonic" integrated circuits. Using light instead of electrical energy for integrated circuits allows for the transmission and processing of information at speeds that are not possible with conventional electronic devices. Researchers say silicon photonics - silicon-based optical circuits - are one of the main platforms for such laser pointer technology because of their compatibility with existing microelectronics.
Peter Rakich, an associate professor of applied physics at Yale University, led the study. He said: "In the past few years we have seen the rapid development of silicon photonics. "We are not only beginning to see these technologies enter commercial products, but also help our data centers be flawless. It runs, and we've also discovered new photonic devices and technologies that can change everything from biosensing to quantum information on the chip. For the field. "
Researchers say that this rapid growth urgently requires new silicon lasers to power new circuits - a problem that has historically been difficult to achieve due to the indirect bandgap of silicon. Nils Otterstrom, a graduate student at Rakich Labs, said: "The inherent properties of silicon are very useful for many chip-scale optical technologies, but using current to generate lasers is very difficult." The first author of the study. "This is a problem that has plagued scientists for more than a decade. To avoid this problem, we need to find other ways to amplify the light on the chip. In our case, we use a combination of light and sound waves."
The laser-designed flag magnifies the light within the shape of the runway - capturing it in a circular motion. “Track design is a key part of innovation, and in this way we can maximize the light and provide the laser pointer to generate the feedback we need,” Otterstrom said.
To amplify the sound, the silicon laser uses a special structure developed by Rakich Labs. "It's basically a nanoscale waveguide designed to strictly limit light and sound waves and maximize their interaction," Rakich said.
"The uniqueness of this waveguide is that there are two different light propagation channels," adds one of the co-authors of the study, and Eric Kittlaus, a graduate student at Rakich Labs. “This allows us to shape photoacoustic coupling in a way that provides a very robust and flexible laser design.”
The researchers explained that without this type of structure, it is impossible to amplify light with sound in silicon. "We used the soft-sound interactions that barely existed in these optical circuits and turned them into the strongest amplification mechanism in silicon," Rakich said. “Now, we can use it for the new laser pointer technology that nobody thought of 10 years ago.”
Otterstrom said there are two main challenges in developing new lasers: "First, design and manufacture devices with amplification that exceed losses, and then find out the counter-intuitive dynamics of the system," he said. "What we observed was that although the system is clearly an optical laser, it also produces very consistent supersonic waves."
The research team said that these attributes could lead to many potential applications, from integrating oscillators to new solutions for encoding and decoding information. Collaborator, Ryan Behunin, an assistant professor at Northern Arizona University and a former Rakich lab member, said: "With silicon, we can create a variety of laser designs, each with unique dynamics and potential applications." The earth expands our ability to control and shape light in silicon photonic circuits. ”