Radiative thermal emission control
10:20 Invited talk : Nanophotonics for Energy Applications
MIT (USA) Certain novel opportunities for exploring nanophotonics (including tailoring thermal radiation, and angular selectivity) for energy applications will be presented.
10:40 : Frequency-Tunable Coherent Thermal Emission from Graphene Coated Silicon Carbide Grating Metamaterials
Yue Yang, Hao Wang, Liping Wang
Arizona State University (USA) We numerically demonstrate frequency-tunable coherent thermal emission from graphene coated silicon carbide (SiC) grating metamaterials. Rigorous coupled-wave analysis shows emission peaks associated with magnetic polariton, whose resonance frequency can be dynamically tuned by varying graphene chemical potential. The underlying physical mechanism is elucidated, while the geometric and directional effects on the selective emission peaks are explored. The metamaterial structures coated with multiple graphene sheets are further investigated to achieve a larger tunability up to 8.5 percent in peak frequency.
10:55 Invited talk : Thermal emission control by manipulating electronic and photonic states: Energy Recycling and Dynamic Control
Susumu Noda, M. D. Doysa, T. Inoue, T. Asano
Kyoto University (Japan) We describe thermal emission control by manipulating electronic and photonic states, more concretely, using an intersubband transition in quantum well and a photonic- crystal band-edge resonant effect. We show that the thermal emission peak intensity can be more than four times greater than that of a reference blackbody sample under the same input power and thermal management conditions.
11:15 Invited talk : Thermal Beaming
ETH Zurich (Switzerland) We will discuss tailored thermal emission from periodic metallic structures. First, we will describe experiments on tungsten bull's eyes on which surface plasmon polaritons are excited at elevated temperatures. In the direction normal to the film, a spectrally narrow beam of thermal emission is observed at a wavelength equal to the spacing between the grooves. Second, we will describe a simple layered structure that is being explored as the selective emitter in a hybrid thermophotovoltaic device.
11:35 Invited talk : Controlling Thermal Emission Using Photonic Structures for Radiative Cooling
Aaswath Raman, Linxiao Zhu, Shanhui Fan
Stanford University (USA) The cold of outer space is a heat-sink for energy processes on Earth that can be accessed by thermal emission from a sky-facing surface. We first show that to maximally achieve radiative cooling through this mechanism, a selective emitter is necessary due to spectral features of atmospheric emissivity in the mid-infrared. We next report the first experimental demonstration of radiative cooling in the daytime using a photonic design that is both a selective thermal emitter and strong solar reflector.
11:55 Invited talk : Engineering of optical absorption and radiative thermal emission using vanadium dioxide
Mikhail A. Kats
University of Wisconsin (USA) I will discuss the use of vanadium dioxide (VO2) to achieve anomalous and thermal emission properties. The temperature-driven insulator-to-metal transition in VO2 results in widely-varying optical properties in the infrared, making it an excellent material for thermal emission engineering. We demonstrated structures with regions of negative differential thermal emission (emission inversely proportional to temperature) and super-positive differential thermal emission. Modifying the phase change properties of VO2 by doping provides a mechanism for custom design of thermal emission.
12:15 Invited talk : Energy Manipulation in NanoScale Using Thermoplasmonics
American University in Cairo (Egypt) In this work, we propose a detailed study of various novel waveguides made using doped semiconductors at the mid-and far infrared ranges. These waveguides support a plasmonic-like mode with ability to confine the electromagnetic field at nanoscale in these wavelength ranges. The ability to control and harvest the thermal energy using Nanoantenna made using these structures are also demonstrated. The integration of thermal control devices on the same chip with photonic and electric devices is also demonstrated.