Focusing semiconductor lasers usually requires bulky optical lenses acting as a "collimator." Researchers have now demonstrated a plasmonic collimator that utilizes grooves etched directly into the semiconductor laser facet. If the technique is adopted -- Harvard University has applied for a patent on the process -- then semiconductor lasers can be downsized to a bare die without a lens. Eventually the team at Harvard and Hamamatsu Photonics (Hamamatsu City, Japan) hope to demonstrate electrically-controlled polarization of laser beams for use in spintronics and quantum computing.
Text: http://www.eetimes.com/showArticle.jhtml?articleID=209800332
