{"72782":{"#nid":"72782","#data":{"type":"news","title":"Optical Breakthrough Makes \u0022Lab-on-a-Chip\u0022 Possible","body":[{"value":"\u003Cp\u003EGeorgia Tech researchers have found a way to shrink all the sensing power of sophisticated biosensors - such as sensors that can detect trace amounts of a chemical in a water supply or a substance in your blood - onto a single microchip.\u003C\/p\u003E\n\u003Cp\u003EIn compact communication, signal processing and sensing optics technologies, multiple wavelengths of light are combined as a space-saving measure as they carry information. The wavelengths must then be separated again when they reach their destinations. Wavelengths used for these sophisticated applications have very high spectral resolution, meaning the distance between wavelengths is very small. The device that sorts out these crowded wavelengths is called a wavelength-demultiplexer (WD).\n\u003C\/p\u003E\n\u003Cp\u003ECompact optical WDs are key in spectral analysis for biosensers small enough to fit on a chip and for integrated circuits for optical information processing.\n\u003C\/p\u003E\n\u003Cp\u003EGeorgia Tech researchers have designed a WD able to function at very high resolution in much tighter confines (as small as 64 microns by 100 microns - smaller than a millimeter) by developing a new design for photonic crystals, which are highly periodic structures typically etched in very thin silicon that are designed to control light and have the potential to revolutionize everything from computing to communications. The research had been published in Laser Focus World and Optics Express and was recently presented at the Conference on Lasers and Electro-Optics (CLEO 2006).\n\u003C\/p\u003E\n\u003Cp\u003E\u0022We believe we have developed the most compact WD that has been reported to date,\u0022 said Ali Adibi, a professor in Georgia Tech\u0027s School of Electrical and Computer Engineering and the lead researcher on the project. \u0022If you want to have many optical functions on a single micro- or nano-sized chip, you have to be able to practically integrate all those functions in the smallest amount of space possible. Our WD solves many problems associated with combining delicate optical functions in such a small space.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EThe Georgia Tech team was able to shrink its WD by combining into one crystal three unique properties of photonics crystals - the superprism effect (separating wavelengths much more finely than a regular prism), negative diffraction or focusing (reversing the expansion of the light beam and focusing it back to its original size after interacting with the material being analyzed) and negative refraction (filtering wanted and unwanted wavelengths).\u003C\/p\u003E\n\u003Cp\u003EBy combining these effects, Georgia Tech\u0027s WD takes an expanded beam of light and instead of expanding it further as wavelengths are separated, focuses the wavelength into different locations. The structure simultaneously separates wavelengths, focuses wavelengths instead of refracting them and then separates the wavelengths in one structure, solving the problems associated with wavelength interference without adding extra devices to the system.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022This project really demonstrates the importance of dispersion engineering in photonic crystals - and it\u0027s all done by changing the geometry of some holes you etch in the silicon. It\u0027s very simple and it allows you to combine properties into one material that you never could before,\u0022 Adibi said.\n\u003C\/p\u003E\n\u003Cp\u003EDespite the more advanced capabilities of the photonic crystals used in Georgia Tech\u0027s WD, they are no more complex or difficult to manufacture than conventional photonic crystals, Adibi added.\n\u003C\/p\u003E\n\u003Cp\u003EThe team members created these newly optimized crystals by using a modeling tool they developed two years ago to test the properties of a material much faster than time-consuming conventional numerical methods. \n\u003C\/p\u003E\n\u003Cp\u003EThe result is a WD that is less than a millimeter in all dimensions rather than the several centimeters of other currently available WDs. Furthermore, Georgia Tech\u0027s WD can be integrated for several other functionalities on a single chip for signal processing, communications, or sensing and lab on-a-chip applications.  \n\u003C\/p\u003E\n\u003Cp\u003EThe work was supported by the Air Force Office of Scientific Research (AFOSR, G. Pomrenke) and in part by the National Science Foundation (NSF) and David and Lucile Packard Foundation.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Compact device can pack big sensing power on a chip"}],"field_summary":[{"value":"Georgia Tech researchers have found a way to shrink all the sensing power of sophisticated biosensors - such as sensors that can detect trace amounts of a chemical in a water supply or a substance in your blood - onto a single microchip.","format":"limited_html"}],"field_summary_sentence":[{"value":"Compact device can pack big sensing power on a chip"}],"uid":"27281","created_gmt":"2006-08-01 00:00:00","changed_gmt":"2016-10-08 03:01:42","author":"Lisa Grovenstein","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2006-08-02T00:00:00-04:00","iso_date":"2006-08-02T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"72783":{"id":"72783","type":"image","title":"Photonic crystal design","body":null,"created":"1449177954","gmt_created":"2015-12-03 21:25:54","changed":"1475894665","gmt_changed":"2016-10-08 02:44:25"},"72784":{"id":"72784","type":"image","title":"Ali Adibi","body":null,"created":"1449177954","gmt_created":"2015-12-03 21:25:54","changed":"1475894665","gmt_changed":"2016-10-08 02:44:25"}},"media_ids":["72783","72784"],"groups":[{"id":"1214","name":"News Room"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003ELisa Grovenstein\u003C\/strong\u003E\u003Cbr \/\u003ECommunications \u0026amp; Marketing\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=lgrovenste3\u0022\u003EContact Lisa Grovenstein\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-8835\u003C\/strong\u003E","format":"limited_html"}],"email":["lisa.grovenstein@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}