劳伦斯伯克利国家实验室Hanwei Gao博士学术报告通知
报告题目：Cleaved-Coupled Nanowire Lasers
报告人： Ph.D. Hanwei Gao
报告时间：2013年5月13日上午 10:00-11:00
报告地点：教三326
报告时间：2013年5月13日上午 10:00-11:00
报告地点：教三326
报告摘要:
Semiconductor nanowires with high optical gain offer promising solutions for lasers with small footprints and low power consumption. Although much effort has been directed towards controlling their size, shape, and composition, most nanowire lasers currently suffer from emitting at multiple frequencies, arising from the longitudinal modes native to simple Fabry-Pérot cavities. Here we demonstrate spectral manipulation of lasing modes by axially coupling two nanowire cavities through a nanoscale gap. Lasing operation at a single ultraviolet wavelength at room temperature was achieved in cleaved-coupled GaN nanowires with a lower threshold gain than that of the individual component nanowires. Good agreement was found between the measured lasing spectra and the predicted spectral modes obtained from simulated optical coupling properties, which presents design principles for rational control over the lasing modes in cleaved-coupled nanowire lasers. The highly monochromatic light from coupled nanowire lasers is anticipated to provide ultra-compact photon sources for laser-based remote sensing, high-density optical data storage, and long-distance optical communication.
Semiconductor nanowires with high optical gain offer promising solutions for lasers with small footprints and low power consumption. Although much effort has been directed towards controlling their size, shape, and composition, most nanowire lasers currently suffer from emitting at multiple frequencies, arising from the longitudinal modes native to simple Fabry-Pérot cavities. Here we demonstrate spectral manipulation of lasing modes by axially coupling two nanowire cavities through a nanoscale gap. Lasing operation at a single ultraviolet wavelength at room temperature was achieved in cleaved-coupled GaN nanowires with a lower threshold gain than that of the individual component nanowires. Good agreement was found between the measured lasing spectra and the predicted spectral modes obtained from simulated optical coupling properties, which presents design principles for rational control over the lasing modes in cleaved-coupled nanowire lasers. The highly monochromatic light from coupled nanowire lasers is anticipated to provide ultra-compact photon sources for laser-based remote sensing, high-density optical data storage, and long-distance optical communication.
报告人简介:
Dr. Hanwei Gao received his B.S. in Physics from University of Science and Technology of China in 2004 and his Ph.D. in Materials Science from Northwestern University in 2009. Since 2010, Dr. Gao worked at University of California-Berkeley Postdoctoral Researcher under the supervision of Prof. Peidong Yang with his research focusing on plasmonic enhanced solar energy devices, both photovoltaics and photoelectrochemical water splitting. Dr. Gao was a recipient of the Water P. Murphy Fellowship and the National Science Foundation Materials Research and Engineering Center Fellowship. He has published more than twenty articles in journals including Nature Nanotechnology, Proceedings of the National Academy of Sciences USA, Nano Letters, etc.
Dr. Hanwei Gao received his B.S. in Physics from University of Science and Technology of China in 2004 and his Ph.D. in Materials Science from Northwestern University in 2009. Since 2010, Dr. Gao worked at University of California-Berkeley Postdoctoral Researcher under the supervision of Prof. Peidong Yang with his research focusing on plasmonic enhanced solar energy devices, both photovoltaics and photoelectrochemical water splitting. Dr. Gao was a recipient of the Water P. Murphy Fellowship and the National Science Foundation Materials Research and Engineering Center Fellowship. He has published more than twenty articles in journals including Nature Nanotechnology, Proceedings of the National Academy of Sciences USA, Nano Letters, etc.
Starting August 2013, Dr. Gao will join the Physics Faculty at Florida State University. Multiple graduate and postdoctoral researcher positions will be available in his research group. Motivated candidates with interest in experimental condensed matter and material physics are encouraged to contact him.
