Smallest room-temperature IR laser

BBC : Nanoscale lasers that operate at room temperature and in the IR waveband have been built by Mercedeh Khajavikhan of the University of California, San Diego, and her colleagues. Almost all lasers need a certain amount of energy input—the threshold—before the light waves they produce combine and form a laser beam. Until now, decreasing the size of the laser increased the required energy to the point that the devices weren’t practical. To get around this unfavorable tradeoff, Khajavikhan built the laser cavities with a cylindrical or co-axial shape, rather than a box-like shape as in previous attempts. Although the first batch used energy from a large laboratory laser, the next step will be to adjust the lasers so they use electricity. Once that’s accomplished, the devices will have potential applications in optical computing and telecommunications; lasers can carry information much faster than traditional semiconductor electronics.