BIC laser could enhance medical procedures, telecommunications and computing.
University of California San Diego researchers have presented a laser based on bound states in the continuum (BICs), an unconventional wave physics phenomenon. This is the first BIC laser in the world.
BICs defy the norm of conventional waves, which escape in an open system. In contrast, BICs remain localized or confined despite the open pathways.
The laser has a thin semiconductor membrane—made of gallium, phosphorous, arsenic and indium—constructed as an arrangement of nano-sized cylinders. The membrane is suspended in air and a network of supporting bridges interconnect with its cylinders, providing stability.
With such unique properties, BIC lasers can be adjusted to emit light beams of various wavelengths. This can prove useful in the medical field when precisely targeting cancer cells.
The BIC system was able to emit a low frequency laser beam of its own when researchers used a high frequency laser beam to power the membrane. The lower frequency beam was consistent with telecommunication frequency.
BICs can also enable more powerful optical communication systems and computers—carrying up to 10 times more information compared to current methods—by emitting specific vector beams.
The size of the system can also be scaled up to produce high power lasers for defense and industrial applications. Boubacar Kanté, electrical engineering professor, UC San Diego Jacobs School of Engineering, who led the research said, “A fundamental challenge in high power lasers is heating and with the predicted efficiencies of our BIC lasers, a new era of laser technologies may become possible.”
“Right now, this is a proof of concept demonstration that we can indeed achieve lasting action with BICs,” said Kanté, “…And what’s remarkable is that we can get surface lasing to occur with arrays as small as 8 x 8 particles.”
The popular VCSELs (vertical-cavity surface-emitting lasers) used in high-precision sensing and data communications require much more power and need about 100 times larger arrays than the potential ‘BICSEL’ (bound state in the continuum surface-emitting laser). With hopes of replacing VCSELs with BICELs someday, the team has filed a patent. This new type of light source could accompany smaller devices that will require less power.
The next step for Kanté’s team is to create electrically powered BIC lasers, rather than their current optically powered system . “An electrically pumped laser is easily portable outside the lab and can run off a conventional battery source,” Kanté said.
For more information, visit their published work in the journal Nature.