Lasers are used in several applications including medical equipment, satellites and automobiles, but smaller and more powerful lasers could open up a number of new possibilities.
An international team has developed a high-powered, randomly polarized laser beam that emits light pulses so brief they are measures in nanoseconds.
The researchers published their results in Scientific Reports.
“The experimental evidence provided in this study advances this research field toward the realization of actively controllable integrated micro lasers,” Taichi Goth, the second author of the paper and an assistant professor in the department of electrical and electronic information engineering at the Toyohashi University of Technology in Japan, said in a statement.
The researchers used Q switch lasers, which can produce more precise results with less damage than traditional tools. The lasers, which are often used in surgical procedures, require integration of active and passive responsibilities for maximum efficiency.
“There are two advantages to actively controlling integrated micro lasers,” Goto said. “The size is small, and mass production technique can be used. The price of one piece of Q switch laser can be decreased by the integration.”
The researchers used a technique called Q switching to produce short, but high-powered pulse outputs. Similar to other lasers, an electric current excites electrons in a laser medium—in this case, a crystal used in solid-state lasers—and emits the resulting energy as amplified light. The light can be polarized in one direction or another, but it is nearly impossible to change the randomly polarized light in a small Q switch laser.
However, the researchers used Q switching, coupled with a laser a tenth of the size of a penny, to produce a laser beam ten times more powerful than the previously reported laser beam produced by a larger laser.
The scientists also adjusted the magnetic material the light travels through and amplified it to a more powerful pulse.
The researchers could also use magneto-optics with the addition of a neodymium-yttrium-aluminum garnet to better control how the light moves within the laser cavity.
The short pulses allow the researchers to change the polarization of the laser through manipulation of the photons comprising the light. Rather than a constant light, each pulse can be switched. The laser size means the energy punches out, instead of dissipating as it travels inside the system.
The next step will be to increase the peak power of the system and apply the system as an integrated micro laser for further testing.
The study was published in Scientific Reports.
