Guest_Jim_* Posted February 18, 2016 Posted February 18, 2016 We are quickly approaching a wall that modern electronics cannot surpass due to the physical limitations of the materials used. Some new technology will be necessary to continue increasing computing power and among the possibilities is photonics, which use light to transmit information instead of electricity. To make photonics possible though, we need to ability to attach light sources to silicon and now researchers at the Technical University of Munich have found a way to do just that. The light sources in this case are nanowire lasers, which create the coherent light by reflecting photons off of the top and bottom of the wires, amplifying the light until it can start lasing. The nanowires are made from gallium arsenide, which normally cannot be grown on silicon, because the two materials have different lattice structures and expand differently when heated. Also the interface between the silicon and gallium arsenide is not reflective enough for a nanowire laser. The solution to both problems was to add a 200 nm layer of silicon oxide on top of the silicon. Small holes can then be precisely etched into this layer so that the nanowires will grow vertically from them. This reduces the footprint and thus the strain the nanowires will endure, while also providing the desired mirror surface. The next step for this work is to find a means to power the nanowire lasers electrically, instead of requiring an external laser to pump in the energy. Also the researchers want to be able to control the light emitted by the lasers, which is currently limited to a predefined infrared wavelength. Source: Technical University of Munich Back to original news post Share this post Link to post Share on other sites More sharing options...
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