Alexander Lochbaum's Article on Front Cover in ACS Photonics


The article On-Chip Narrowband Thermal Emitter for Mid-IR Optical Gas Sensing by Alexander Lochbaum et. al. demonstrate a CMOS-compatible mid-infrared emitter with applications in the field of low-cost, optical, gas sensing.

Front Cover Pic
Concept of metamaterial perfect emitter (MPE) light source. Illustration of the MPE light source in an exploded view (dimensions not to scale). The MPE structure is deposited in a series of postprocessing steps on top of a MEMS hotplate.

Efficient light sources compatible to complementary metal oxide semiconductor (CMOS) technology are key components for low-cost, compact mid-infrared gas sensing systems. In this work we present an on-chip narrowband thermal light source for the mid-infrared wave-length range by combining microelectromechanical system (MEMS) heaters with metamaterial perfect emitter structures.

Exhibiting a resonance quality factor of 15.7 at the center wavelength of 3.96 μm and an emissivity of 0.99, the demonstrated emitter is a spectrally narrow and efficient light source. We show temperature-stable (resonance wavelength shift 0.04 nm/°C) and angular-independent emission characteristics up to angles of 50° and provide an equivalent circuit model illustrating the structure’s resonance behavior. Owing to its spectrally tailored, nondispersive emission, additional filter elements in a free-space optical gas sensing setup become obsolete. In a proof-of-concept demonstration of such a filter-free gas sensing system with CO2 concentrations in the range of 0−50000 ppm, we observe a 5-fold increase in relative sensitivity compared to the use of a conventional blackbody emitter. Our light source is fully compatible with standard CMOS processes and tunable in emission wavelength through the mid-infrared wavelength band. It paves the way for a new class of highly integrated, low-cost optical gas sensors.

Alexander Lochbaum, Yuriy Fedoryshyn, Alexander Dorodnyy, Ueli Koch, Christian Hafner and Juerg Leuthold, ACS Photonics, 4 (6): 1371-1380, Washington, DC: American Chemical Society, 2017. DOI  Research Collection


Page URL:
Fri Jul 21 21:55:03 CEST 2017
© 2017 Eidgenössische Technische Hochschule Zürich