UC San Diego Engineers Demonstrate Smallest Laser to Operate at Room Temperature

UCSD Ultrafast and Nanoscale Optics Group Nanoscale Architecture for Coherent Hyper-Optic Sources (NACHOS) DARPA Microsystems Technology Office Defense Advanced Research Projects Agency (DARPA) Calit2 Jacobs School of Engineering Electrical and Computer Engineering Department Measuring the etch depth of a sample using the WYKO optical profilometer in Calit2's Nano3 facility. (l-r) assistant project scientist Maziar Nezhad, Nano3 manager Bernd Fruhberger, and ECE graduate student Olesya Bondarenko. Imagine packing 4 billion nanolasers on a three-inch semiconductor wafer. That is now nearer to reality, thanks to researchers at the University of California, San Diego's Jacobs School of Engineering, who have demonstrated a micron-sized laser ' less than one-thousandth of a millimeter on each side - that can operate at room temperature. Until now, the only way to operate such a nanolaser was to cool it cryogenically to offset the various losses in the device. The UCSD solution, as published online in advance of appearing in the May issue of * , was to add super-thin layers of silica (glass) and aluminum to encase the core of each device. 'Shrinking the size of lasers to below their wavelength of emission has been challenging historically,' said Yeshaiahu (Shaya) Fainman, principal investigator on the project and a Cymer professor in UC San Diego's Electrical and Computer Engineering (ECE) department.