In this study, the bending losses of chalcogenide glass channel optical waveguides consisting of an As2Se3 core and an As2S3 lower cladding layer were numerically evaluated across the astronomical N-band, which is the mid-infrared spectral range between the 8 µm and 12 µm wavelengths. The results reveal the design rules for bent waveguides in mid-infrared astrophotonic devices.

In this study, we conduct guided mode analyses for chalcogenide glass channel waveguides using As2Se3 core and As2S3 lower cladding to determine their single-mode conditions across the astronomical N-band (8-12µm). The results reveal that a single-mode operation over the band can be achieved by choosing a suitable core-thickness.

Development of narrowband thermal emitters whose emission wavelengths are dynamically tunable is highly desired for various applications including the sensing of gases and chemical compounds. In this paper, we review our recent demonstration of wavelength-switchable mid-infrared thermal emitters based on multiple quantum wells (MQWs) and photonic crystals (PCs). Through the control of absorptivity by using intersubband transitions in MQWs and optical resonances in PC slabs, we demonstrate novel control of thermal emission, including realization of high-Q (Q>100) thermal emission, dynamic control of thermal emission (∼MHz), and electrical wavelength switching of thermal emission from a single device.