Speaker: Professor Sir John Pendry, Imperial College London, United Kingdom
Date: 30 Nov 2015 (Monday) Time: 10:00 am to 11:00 am Venue: Lee Foundation Lecture Theatre, Wee Kim Wee School of Communication And Information (WKWSCI), WKWSCI-01-LT1 Abstract Metamaterials: we control electromagnetic radiation in general and light in particular by exploiting the properties of materials and their response to electric and magnetic fields. Glass refracts light because of its response to electric fields and can be used to focus light – hence much of the optics industry. However nature has provided us with a limited palette of properties, much more restricted than allowed in principle by the laws of physics. The response of conventional materials to electromagnetic fields is determined by their constituent molecules. In contrast metamaterials owe their properties to much larger units, though still less than the wavelength of radiation. These large structural units, or ‘metamolecules’ can be designed to give a much wider spectrum of properties. In fact almost any property allowed by physical laws can in principle be engineered in this way. The development of these new materials will be traced and examples given. Transformation optics: our intuitive understanding of light has its foundation in the ray approximation and is intimately connected with our vision: as far as our eyes are concerned light behaves like a stream of particles. Here we look inside the wavelength and show how the new concept of transformation optics that manipulates electric and magnetic field lines rather than rays can provide an equally intuitive understanding of sub wavelength phenomena and at the same time be an exact description at the level of Maxwell’s equations. Invisibility: Hiding an object presents two challenges: the object must not be seen and surrounding objects must not be obscured. In other words the hidden object must not cast a shadow. This latter requirement presents a challenge because light incident on the cloak must be captured, preserved, and steered around the cloak to emerge on the same trajectory it had before it hit the cloak. Transformation optics is the ideal tool for this design challenge. Speaker’s Biography Prof Sir John Pendry is the Chair in theoretical solid-state physics at Imperial College London. He is the Fellow of the Royal Society, Fellow of the Institute of Physics, Fellow of American Academy of Arts and Sciences, and Foreign Associate of the US National Academy of Sciences, etc. In 2004, he was knighted in the British Honours for his services to science. In a career spanning nearly 50 years, Prof Pendry has worked on the physics of surfaces, disordered systems, and novel photonic materials. He is the pioneer of “metamaterials”, a concept for engineered structures that respond to electromagnetic waves in unusual ways. This research has led to the experimental realizations of negative refraction, perfect lenses, invisibility cloaks, and other remarkable electromagnetic devices. Prof Pendry has won several awards, including the Dirac Medal in 1996, the Royal Medal in 2006, the UNESCO Niels Bohr gold medal in 2009, the Isaac Newton Medal in 2013, and the Kavli Prize in Nanoscience 2014, etc. Jointly organized by OPTIMUS/ COFT/Si COE, School of EEE College of Engineering & The Photonics Institute, Nanyang Technological University IEEE Photonics Society Singapore Chapter
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AuthorIEEE IPS Singapore Chapter Archives
October 2019
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