Full 3-D Invisibility Cloak in Visible Light
Source Newsroom: American Institute of Physics (AIP)
Newswise — Washington, D.C. (April 28, 2011) -- Watching things disappear “is an amazing experience,” admits Joachim Fischer of the Karlsruhe Institute of Technology in Germany. But making items vanish is not the reason he creates invisibility cloaks. Rather, the magic-like tricks are attractive demonstrations of the fantastic capabilities that new optical theories and nanotechnology construction methods now enable.
This new area, called “transformation optics” has turned modern optical design on its ear by showing how to manipulate light in ways long thought to be impossible. They promise to improve dramatically such light-based technologies as microscopes, lenses, chip manufacturing and data communications.
In his talk at this year's Conference on Lasers and Electro Optics (CLEO: 2011, May 1 - 6 in Baltimore), Fischer will describe the first-ever demonstration of a three-dimensional invisibility cloak that works for visible light—red light at a wavelength of 700 nm—independent of its polarization (orientation). Previous cloaks required longer wavelength light, such as microwaves or infrared, or required the light to have a single, specific polarization.
Fischer makes the tiny cloak—less than half the cross-section of a human-hair—by direct laser writing (i.e. lithography) into a polymer material to create an intricate structure that resembles a miniature woodpile. The precisely varying thickness of the “logs” enables the cloak to bend light in new ways. The key to this achievement was incorporating several aspects of a diffraction-unlimited microscopy technique into the team’s 3-D direct writing process for building the cloak. The dramatically increased resolution of the improved process enabled the team to create log spacings narrow enough to work in red light.
“If, in the future, we can halve again the log spacing of this red cloak, we could make one that would cover the entire visible spectrum,” Fischer added.
Practical applications of combining transformation optics with advanced 3-D lithography (a customized version of the fabrication steps used to make microcircuits) include flat, aberration-free lenses that can be easily miniaturized for use in integrated optical chips, and optical “black holes” for concentrating and absorbing light. If the latter can also be made to work for visible light, they will be useful in solar cells, since 90 percent of the Sun’s energy reaches Earth as visible and near-infrared light.
Presentation QTuG5 “Three-dimensional invisibility carpet cloak at 700 nm wavelength,” by Joachim Fischer et al. is at 11 a.m. Tuesday, May 3. Fischer et al. will also present CML1, “Three-Dimensional Laser Lithography with Conceptually Diffraction-Unlimited Lateral and Axial Resolution,” at 10:15 a.m. Monday, May 2.
CLEO: 2011 Program Information
CLEO: 2011 unites the fields of lasers and optoelectronics by bringing together all aspects of laser technology, from basic research to industry applications. The main broad topics areas at the meeting are fundamental science, science and innovations, applications and technology, and market focus. An exposition featuring 300 participating companies will be held concurrently with the scientific presentations.
Plenary Session keynote speakers include Donald Keck, retired vice president of Corning, talking about making the first low-loss optical fibers; James Fujimoto of MIT, talking about medical imaging using optical coherence tomography (OCT); Mordechai (Moti) Segev of the Technion-Israel Institute of Technology, speaking about the localization of light; and Susumu Noda of Kyoto University, talking about the control of photons in photonic crystals.
• Conference program: http://www.cleoconference.org/Conference_Program
• CLEO: Expo: http://www.cleoconference.org/exhibit_hall
• Press Center: http://www.cleoconference.org/media_center
• Plenary Session: http://www.cleoconference.org/Conference_Program
• Special Symposia: http://www.cleoconference.org/Conference_Program/symposia.aspx
• Conference Registration: http://www.cleoconference.org/registration
A Press Room for credentialed press and analysts will be located on-site in the Baltimore Convention Center, Sunday, May 1 – Thursday, May 5. Media interested in attending the conference should register online at http://www.cleoconference.org/media_center/mediaregistrationform.aspx or contact Angela Stark at 202.416.1443, firstname.lastname@example.org.
With a distinguished history as the industry's leading event on laser science, the Conference on Lasers and Electro-Optics (CLEO) and the Quantum Electronics Laser Science Conference (QELS) is where laser technology was first introduced. CLEO: 2011 will unite the field of lasers and electro-optics by bringing together all aspects of laser technology, with content stemming from basic research to industry application. Sponsored by the American Physical Society's (APS) Laser Science Division, the Institute of Electronic Engineers (IEEE) Photonics Society and the Optical Society (OSA), CLEO: 2011 provides the full range of critical developments in the field, showcasing the most significant milestones from laboratory to marketplace. With an unparalleled breadth and depth of coverage, CLEO: 2011 connects all of the critical vertical markets in lasers and electro-optics. For more information, visit the conference's website at www.cleoconference.org.