Bong Jae Lee

The present paper theoretically demonstrates coherent thermal emission in the infrared region by exciting magnetic polaritons between metallic gratings and an opaque metallic film, separated by a dielectric spacer. The coupling of the metallic strips and the film induces a magnetic response that is characterized by a negative permeability and positive permittivity. On the other hand, the metallic film intrinsically exhibits a negative permittivity and positive permeability in the near infrared.

The present study reports a novel concept of a direct solar thermal collector that harnesses the localized surface plasmon of metallic nanoparticles suspended in water. At the plasmon resonance frequency, the absorption and scattering from the nanoparticle can be greatly enhanced via the coupling of the incident radiation with the collective motion of electrons in metal. However, the surface plasmon induces strong absorption with a sharp peak due to its resonant nature, which is not desirable fo

Coherent thermal emission from surface relief gratings holds promise for spectral and directional control of thermal radiation but is limited to transverse magnetic waves, which can excite surface plasmon or phonon polaritons in the grating structure. We show in this letter that a coherent thermal source can be constructed with a thin polar material coated on a one-dimensional photonic crystal. The excitation of surface waves at the interface of the coated layer and the photonic crystal results

A large number of recent publications dealt with enhanced emission properties of micro/nanostructures by the excitation of surface plasmon or phonon polaritons. Some used grating structures to demonstrate coherent thermal emission in a narrow spectral band and towards a well-defined direction. Others suggested that planar layers could also be used to achieve coherent emission. In the present paper, we describe two alternative designs with fewer layers for the application as coherent emission sou

Enhancement of thermal emission and control of its direction are important for applications in optoelectronics and energy conversion. A number of structures have been proposed as coherent emission sources, which exhibit a large emissivity peak within a narrow wavelength band and at a well-defined direction. A commonly used structure is the grating, in which the excited surface polaritons or surface waves are coupled with propagating waves in air, resulting in coherent emission for p polarization

Achieving high-accuracy temperature measurements in rapid thermal processing using radiation thermometry requires knowledge of the optical properties of silicon and related materials, such as silicon dioxide, silicon nitride, and polysilicon. However, available optical property models lack consistency and are not fully validated by experiments at the wavelength and temperature ranges critical to radiation thermometry. A critical survey is given of the existing optical models, with emphasis on th

The direct utilization of solar radiation has been considered a promising energy source because of its abundance, sustainability, and cleanness. The conversion of solar radiation into usable heat largely depends on the absorption characteristics of a solar thermal collector. In the present study, we conducted design analysis of a wavelength-selective absorber composed of a two-dimensional Nickel grating, a thin SiO2 film, and a Nickel substrate. Dimensions of the two-dimensional grating were det