High-quality large-scale electron-beam-written resonant filters for the long-wave infrared region
Abstract
We present new, to the best of our knowledge, large-scale, high-quality spectral filters operating in the long-wave infrared (LWIR) spectral region. We employ high-spatial resolution nanofabrication techniques to achieve large-area ( 12 m m × 12 m m ) spectrally tunable notch filters. Filter operation is based on the guided-mode resonance effect. The device structure consists of a germanium waveguide grating on top of a zinc selenide substrate. The filters reflect the incident broadband light at one (or more) narrow spectral bands while fully transmitting the rest. We tune the reflected wavelength by tilting the filter. Filters based on one-dimensional gratings are polarization sensitive. We fabricate prototype filters and characterize their polarization dependence and spectral tuning performance using a tunable quantum cascade laser system that spans the ∼ 7 − 13 µ m spectral band. We obtain an excellent agreement between the theoretical and experimental results.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 11, 2021
- Source ID
- 10.1364/ol.415866
Entities
People
- Junyeob Song
- Neelam Gupta
Organizations
- United States Army Research Laboratory