Physics Seminar which might interest your students and faculty

Greetings,

The regular Physics Seminar meets Thursday March 31 PC 2212 at 4pm.

Tomorrow we explore the world of Photon Polaritons with a talk by Prof. James Hammonds from Howard University.  

The title of his talk is:
     Preliminary Investigation of Photon Polariton Modes
         in an Asymmetric Multilayer Planer Structure

Dr. Hammonds is from the Department of Mechanical Engineering at Howard University.
His talk will be on:

Surface phonon polaritons (SPhP) are wave modes that do not usually participate in thermal radiative energy exchange since they are bound to surfaces and interfaces.  In this work we show preliminary experimental and analytical results that demonstrate how a multilayered structure consisting of a negative dielectric material sandwiched between two positive dielectric materials with asymmetric optical properties, may be used to couple the SPhP into radiative modes that can participate in energy transport.  Silicon carbide is a key material of interest since it is a negative dielectric in the infrared, and thus has particular relevance in low-temperature radiation heat transfer.  The infrared reflectance of the multilayer structure is studied experimentally using Fourier transform infrared spectroscopy (FTIR).  We then analytically determine the surface phonon polariton (SPhP) mode dispersion relation for the geometry through which we clarify the role radiative SPhP modes play in the multilayer emissive properties.  Finally, we discuss how the radiative SPhP modes can strongly impact near-field thermal radiation heat transfer in the multilayer geometry.