Further Investigation of Coherent Thermal Emission from Single Negative Materials

Abstract

Planar heterogeneous structures have been proposed to achieve selective spectral and directional emission by using layers of negative permittivity (ε) paired with layers of negative permeability (μ), the so-called single negative materials. The coherent emission of radiation is achieved by the excitation of surface polaritons at the interface between the negative-ε and negative-μ layers and can be obtained for both p and s polarization. In the present work, a detailed study is carried out to investigate the effects of layer thicknesses and other important parameters on the emission characteristics of the planar heterogeneous structures. Furthermore, it is found that proper selection of the parameters of the layered structures can result in quasi-monochromatic but nearly diffuse emission of radiation; this may have potential applications in, for example, thermophotovoltaic devices.

KEY WORDS:

• coherent thermal emission
• metamaterials
• polaritons
• surface waves

The authors thank Bong Jae Lee of Georgia Tech for valuable assistance in preparing this manuscript. This work was supported by the National Science Foundation (CTS-0236831 and CTS-0500113). CJF thanks the National Natural Science Foundation of China (50606001) for the financial support.