SEAS Lab Creates Multibeam Laser

Typical lasers emit one beam of a single, exact wavelength, but a group of researchers have created a new laser that can emit multiple beams of different wavelengths.

This laser has potential applications in areas including pollution detection, climate monitoring, and remote sensing, according to Nanfang Yu, a postdoctoral researcher at the Harvard School of Engineering and Applied Sciences and one of the authors of the study.

“The big deal is that they were able to get a multibeam laser, and a multifunctional laser. It is very difficult to get more than one beam,” said Michael P. Rutter, communications director for SEAS.

The project, which began at the start of the year, was led by Federico Capasso, a professor of applied physics at SEAS, and two international teams—one from Japan and one from Switzerland, according to Yu.

“The project was initiated by the Harvard team,” Yu said. “The other team helped to design and process the lasers.”

The international teams also provided the ultra-thin layers of semiconductor materials, Yu added.

The creation of this laser marks a step forward from the quantum cascade laser, which was invented by Capasso and his collaborators at Bell Labs in 1994, Rutter wrote in a press release.

The researchers said the new laser has potential applications in many areas of environmental science. For example, the lasers could be used to gather information about levels of carbon dioxide and other gases in the atmosphere, Rutter explained. He said that the researchers were “most excited” about the use of the lasers in climate monitoring.

“We wanted to create such devices for remote sensors and to detect pollution in the air,” said Yu.

The next step, according to Yu is to find collaborators both within Harvard and at other universities.

“We want to find other collaborators in the Environmental Engineering department of the School of Engineering and Applied Sciences, or the Chemical department,” said Yu.

The group’s work was featured online in the October 23rd issue of Applied Physics Letters and will appear as a cover story on December 7th.