A University engineering project has successfully demonstrated the first polariton laser.

The laser is powered by electricity, rather than light, and has proven to be far more energy-efficient than conventional lasers. It has the potential to be used in areas where lasers are currently housed — including optical communication for wired Internet. Because of its ability to modulate, the project could make lasers useful in future developments in the consumer electronics field, a University press release reported.

Engineering Prof. Pallab Bhattacharya led a group of four students working on the project. The group has worked on the project since September 2009, and achieved their first successful test in the summer of 2012 before publishing their paper in the fall.

Bhattacharya said the polariton laser will spark more development in the field, and the fact that he and his team were the first to create one is “a big deal.”

“I think this is another completely new kind of a coherent light source with electric injection,” Bhattacharya said.

Bhattacharya discussed the significance of the polariton laser, saying the energy needed to power the laser was “three orders of magnitude lower than the conventional laser.” Though he’s a “physicist at heart,” he hopes to see more engineers get involved in the field to achieve practical uses for the laser.

Although the laser cannot be currently used for high power applications, Bhattacharya said there is a “multitude” of low power applications, including low power switches and low power amplifiers, each requiring a significantly lower input energy than conventional lasers.

Bhattacharya explained that the polariton laser is so efficient because it requires a fewer number of polaritons, and they are all able to occupy the same energy state, called degeneracy, taking up less room.

“Imagine in the football stadium: As people come in, let’s say they occupy the seats in the lowest rows and then they are filled up and they go to the highest seat,” Bhattacharya said. “Well here, some of these polaritons, they can all fit in the lowest level.”

These grouped polaritons then form a condensate, which is coherent and emits coherent light like a laser, Bhattacharya added.

The project reached its major breakthrough with the implementation of a magnetic field, which allowed the laser to work properly.

Rackham student Allan Xiao, one of the students working on the project, said even though the laser is in its “infancy stage,” it’s still a significant breakthrough in laser technology.

“Although our device is only a prototype which requires some external means such as low temperature and an external magnetic field to help it operate it is the first polariton laser that does not require optical pumping with another laser,” Xiao said.

Both Bhattacharya and Xiao said though it’s currently hard to tell the exact future implications of the polariton laser, it has reinvigorated the previously stagnant field.

“This gives us a lot of momentum,” Bhattacharya said, “And as we think of things, and so on, I’m sure I’ll come up with and others will, with new applications, new device designs, all kinds of things. We’ll be improving on this every day.”

Ayan Das, another Rackham student in the University research group, also emphasized that though other groups borrowed the magnetic field technique, the University was the clear pioneer in the polariton project. At the same time, Das saw it as a form of compliment, noting the significance of having their ideas validated by other top researchers using their techniques.