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Scientific Associate of

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ICO Awards

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Nobel Prizes 2014

Blue LEDs: Nobel Prize in Physics 2014

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Isamu Akasaki Hiroshi Amano Shuji Nakamura

The ICO congratulates Isamu Akasaki, from Meijo University, Nagoya, Japan and Nagoya University, Japan, Hiroshi Amano, Nagoya University, Japan; and Shuji Nakamura, Professor of materials and of electrical and computer engineering, Solid State Lighting & Energy Electronics Center of the University of California, Santa Barbara, CA, USA, on being awarded the 2014 Nobel Prize in Physics “for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”. Three decades of efforts to produce bright blue light sources culminated in the early 1990s. Success in achieving high-efficiency required a breakthrough in high-quality crystal growth; basic materials science for the production of GaN-based alloys with different compositions; device physics for advance heterostructure design for their integration into multilayered structures such as heterojunctions and quantum wells; and optical physics for the optimization of light out-cupling. Asaki, Amano and co-workers developed structures based on AlGaN/GaN, while Nakamura and co-workers explored InGaN/GaN and InGaN/AlGaN for producing heterojunctions, quantum wells and multiple quantum wells. Both groups observed blue laser emission based on GaN in 1995-1996.

Blue LEDs were meanwhile the lacking core of nowadays high-efficient white electroluminescent light sources, which have triggered a revolution in the lighting technology by replacing the incandescent bulbs of the last century with white LED lamps. They contribute to large energy savings and due to their low power requirements might be powered by locally generated solar power and provide illumination to over 1.5 billion underserved population around the world who lack access to electricity grids. UV-emitting AlGaN/GaN LEDs are also used for water purification, as UV light destroys the DNA of bacteria, viruses and microorganisms. They also constitute an essential part of all of our display and recording technologies: GaN-based LEDs are used for back-illuminated liquid crystal displays in cell phones, tablets, computers, TV screens, etc., and Blue and UV-emitting GaN diode lasers are used in DVD and blue-ray technologies.

Super-resolved fluorescence Microscopy: Nobel Prize in Chemistry 2014

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Eric Betzig Stefan Hell William E. Moerner

It is with great pleasure that the ICO congratulates the 2014 Nobel Laureates in Chemistry, Eric Betzig, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA; Stefan W. Hell, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany, German Cancer Research Center, Heidelberg, Germany; and William E. Moerner, Department of Chemistry, Stanford University, Stanford, CA, USA, who were awarded "for the development of super-resolved fluorescence microscopy". Prof. Stefan W. Hell, director of the Department of Nano Biophotonics of the Max-Planck-Institute for Biophysical Chemistry in Göttingen Germany was awarded the 2000 ICO Prize in recognition of his innovative work on increasing resolution in far field optical microscopy. Stefan Hell introduced the concept of Stimulated-Emission-Depletion Microscopy (STED) the basic idea of which is to reduce the extent of the focal spot by 'switching off' fluorescence from its rim. He predicted that STED microscopy should break the diffraction barrier in far-field fluorescence microscopy by about five-fold, which he and his collaborators demonstrated experimentally a few years later. They also achieved 3D-imaging of actin filaments and microtubules in fibroblast cells with 4Pi-confocal microscopy, with a 4-fold sharper sectioning than that of high-end confocal microscopy. In addition to the 4Pi and STED techniques, they introduced a multifocal version of multiphoton microscopy, which delivers real-time, direct-view images from the interior of live cells without trading off resolution against speed. With STED, 4Pi, and other techniques inspired by his work, the famous Abbe's resolution limit was overcome and the resolving power of far-field light microscopy was pushed to the tens of nanometer scale.

William E. Moerner is the Harry S. Mosher Professor of Chemistry at Stanford University. In 1989, as a research scientist with the IBM Corporation, Moerner developed a laser-based technique that for the first time allowed the visualization of single fluorescent molecules. Later, while a professor of chemistry at the University of California, San Diego, he realized that there were ways of controlling the fluorescence of certain proteins, ways that later were employed by Hell and Benzig for super-resolution microscope imaging.

Controllable fluorescence was exploited by Eric Betzig’s in his co-invention of photo-activated localization microscopy, or PALM. PALM achieves resolution well beyond the Abbe limit through sub-wavelength position measurements on fluorescing molecules. Betzig, now a member of the research faculty at the Howard Hughes Medical Institute’s Janelia Farm campus in Ashburn, Virginia, built the first PALM imaging system in the living room of his co-inventor Harald Hess.

Far-field fluorescence microscopy is highly relevant to biological sciences because, in contrast to electron, atomic force and near-field optical microscopy, it allows imaging of the interior of living specimens at the submicron scale. Not surprisingly, 3D versions of super-resolving far-field light microscopy, such as provided by confocal and multiphoton fluorescence microscopes, play a key role in uncovering the secrets of life at the sub-cellular level, revealing relationships between structure and function.