Peking University \”Nature\”: photonic technology is expected to greatly promote the development of chips
Grating couplers are widely used in high-performance, high efficiency laser and the optical laser radar antenna or the like of the radiation-way (unidirectional emission) technology is a key technology and large-scale photonic integrated photonic chip. Currently, this technology is mostly achieved specular reflection grating distributed Bragg reflector, a metal reflector like. However, integration, on the mirror not only bulky sheet, complicated structure, high processing difficulty, also introduce additional losses and dispersion. The key question for the integrated photonic device research to be solved, Department of Electronics,, State Key Laboratory of Information Science and Technology Regional Fiber Optic Communication Network and Advanced Optical Communication System Professor Peng Chaofu [ 123] Department of Physics research group at MIT MarinSoljačić professor  , Physics and Astronomy, University of Pennsylvania 123 123 Chen Bo, assistant professor [ 123] cooperation , a new method does not rely on a single layer on a silicon substrate mirror directional radiation be achieved from the perspective of the proposed topology photonics. Relevant research results to \”unidirectional mode resonances observed topology protection\” (Observation of topologically enabled unidirectional guided resonances) in the title, 2020 April 22, published online in \”Nature\” (Nature, Vol. 580 467 – 471 ); Department of Electronics PhD 2015 students Yinxue Fan as the first author for the corresponding author. Peng Chaodeng topological charge from human manipulation, to achieve a special resonance state unidirectional radiation in the photonic crystal plates, i.e., one-side radiation guided mode resonance (unidirectional guided-resonance, UGR) state, in a dimensional photonic crystals by simultaneously broken vertical symmetry inclined side wall and the inner surface of the lack of symmetry of the structure, so that the system continuously integer topological charge carried by the bound state region is split into half-integer topological charge a pair of upper plates and lower two generating radiation side surface sizes. At this time, maintaining the symmetry is broken by adjustingThe control side of the pair of half-integer parameter topological charge the surface of the recombined into an integer topological charge, forming a mirror does not depend on only one surface of the radiating energy toward UGR state. by manipulating the topological charge evolution, to achieve unidirectional mode resonant states TF joint Samples were prepared using the bevel etching process independent development, experimentally observed ratios of up to asymmetric radiation 27.7dB; which means with more than 99.8% of the photon energy of radiation is oriented toward one side, more traditional design improves 1 to 2 orders of magnitude, thus effectively demonstrate the effectiveness and advantages of unidirectional radiation of the guided-mode resonances. The technology is expected to significantly reduce the insertion loss of ports glazing sheet, greatly promote the development of high density optical interconnect and photonic chip technology. In recent years, with the support of the National Natural Science Foundation of China, Ministry of Education, Science Center and other cutting-edge nano photonics, Chao Peng and co-workers have issued a non-Hermitian Fermi arc observation system (Science, 359, 1009 ~ 1012 at a high level academic journals, side by side On the first, March 2018), non-synthetic and real space observed Abelian gauge fields (Science, 365, 1021 ~ 1025, a second author, September 2019), the super high quality and robust scatter topology protection a series of important research results factor guided mode resonances (Nature, 574, 501 ~ 504, corresponding author, October 2019) and other non-Hermitian physics and fusion topology physics, radiation field in order to achieve the regulation to open up a new direction but also as an integrated photonic chip, the optical phased array radar, low power laser, a photonic device to expand the application of bright future. Characters introduction
Chao Peng , Department of Electronics, regional optical fiber communication network and associate professor at the State Key Laboratory of Advanced Optical Communication Systems, Peking University School of Information Science and Technology. 2004 and 2009 has obtained a bachelor\’s degree in physics and a PhD in Communication and Information System in Peking University. 2009-2011 as Special Fellow Japan Society for the Promotion Overseas (JSPS postdoctoral fellow) at Kyoto University. Research focused on the optical fiber sensor devices and systems, devices and nano-optoelectronics applications. 2019 by the National Natural Science Foundation of Outstanding Youth Science Foundation funding.