Bell Labs Claims Record for Mid-IR Diode Laser

ATLANTA, Ga., March 23 -- Bell Labs has unveiled what it says is the world's highest-power mid-infrared semiconductor laser. According to the Lab's Claire Gmachl, the experimental quantum-cascade laser has more than a thousand times the output power of any commercial semiconductor laser operating in the mid-infrared wavelength region.
Pulsed at room temperature, it produces about half a watt of power; in continuous-wave operation and cooled to about 100 degrees below zero Fahrenheit, it produces a full watt. QC lasers operate via electrons cascading down an energy staircase, producing photons as they hit each step along the way. Gmachl demonstrated that adding stages to QC lasers increases their output power. Electrons in the new laser cascade down 75 steps instead of 20 or 30 as in earlier QC lasers.