As a three-dimensional topological phase of matter, Weyl semimetals possess extremely large gyrotropic optical response in the mid-infrared region, leading to the strong chiral anomaly. This study proposes a circular polarizer design with a double-WSM-layer structure. It is theoretically shown that the proposed polarizer possesses a high circular polarization efficiency and high average transmittance in the wavelength region from 9 µm to 15 µm at incidence angles up to 50°. The modified 4 × 4 matrix method is used to calculate the circularly polarized transmittance of Weyl semimetals in thin-film or multilayer structures. The temperature dependence on the transmittance is also examined to demonstrate the flexibility of the proposed polarizer in a varying temperature environment. This study reveals the technological prospect that Weyl semimetals are promising candidates for high-performance circular polarizers in infrared spectroscopy and polarimetry.
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Broadband pyramid antireflective structure on chalcogenide glasses by the hot embossing method for infrared photonics
Pyramidal antireflective structures were produced by hot embossing single- and double-sides of an amorphous GeSe4optical element. The optical performances were measured across the wavelength range from 2 µm to 15 µm. The transmittance at normal incident angle was increased up to 75.6% and 79.8% for single and double-side embossing respectively. The experimental results were in close agreement with simulation performed using the rigorous coupled-wave analysis (RCWA). Theoretical models also predicted well the transmittance changes as a function of incident angle from 0 ° to 50 ° at a fixed laser wavelength of 5.1 µm. A Fabry-Perot interferometer consisting of two single surface embossed samples is proposed.
more » « less- Award ID(s):
- 1640860
- NSF-PAR ID:
- 10369415
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2159-3930
- Page Range / eLocation ID:
- Article No. 1638
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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