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1162-J02-04

High Temperature Plasmonic Photonic Crystal MEMS Emitter Irina Puscasu1,* Edward Johnson,1 Andrew Taylor,1 Brent Schell,1 William Schaich,2 Rana Biswas3 1 ICx., 215 First Street, Cambridge, MA 02142, [email protected] 2 Department of Physics, Indiana University, 701 East Third Street, Bloomington, IN 47405 3 Departments of Physics & Astronomy; Electrical & Computer Engineering, Iowa State University, Ames IA 50014 * [email protected] ABSTRACT We describe a new class of plasmonic photonic crystal emitters integrated into a MEMS platform for high temperature-intensity, high speed, and high efficiency tuned emitting and sensing applications in the infrared. We exploit 2D organized metallodielectric surface structures for angular and spectral control of reflection, absorption and emission from surfaces in the infrared. We have built a FDTD model that incorporates complex frequency dependent properties and provides quantitative agreement with measured spectral data. High temperature materials and special fabrication techniques allow high temperature operation. This technology offers new solutions for spectral control with application in thermophotovoltaic (TPV) energy conversion. Built on a MEMS platform, for thermal isolation from the environment, these devices also modulate at high speed, opening new applications in spectroscopy, infrared imaging, and signaling. Demonstrated wafer-level vacuum sealing improves the wall plug efficiency dramatically. We describe device architecture and fabrication considerations for plasmonic photonic crystal structures which simultaneously act as emitters and sensors in a defined narrow waveband radiation. In particular, this combined capability opens new avenues for research for vital commercial applications such as environmental protection, household safety, bio-hazardous material identification, meteorology and industrial environments.

INTRODUCTION We are focusing here on advances in infrared sources and sensors based on thermal generation of radiation. There has been considerable recent interest in designing systems whose thermal emission/absorption spectra can be molded to exhibit desired features; e.g., to be strong only in isolated, narrow or broad specific bands and to have either a broad or a narrow distribution in angle.i,ii,iii The basic idea is that one can tailor the emission/absorption spectrum by suitably structuring the near-surface region of an emitter. There has also been an increased need for such thermal sources to emit more light and to modulate the emission at increasing speeds. Higher temperature operation brings serious restrictions on the set of materials used, their interface formation within the device and long term stability. Desired higher modulation frequencies requires reduced

thermal mass and constraints the interaction with the environment. Miniaturizing these sources and rendering them highly efficient follows. We exploit various techniques of surface texturing, random and periodic, to achieve angular and spectral control of re