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Chiral metamaterials in the mid-infrared wavelength range have tremendous potential for studying thermal emission manipulation and molecular vibration sensing. Here, we present one type of chiral plasmonic metasurface absorber with high circular dichroism (CD) in absorption of more than 0.56 across the mid-infrared wavelength range of 5–5.5 µm. The demonstrated chiral metasurface absorbers exhibit a maximum chiral absorption of 0.87 and a maximum CD in absorption of around 0.60. By adjusting the geometric parameters of the unit cell structure of the metasurface, the chiral absorption peak can be shifted to different wavelengths. Due to the strong chiroptical response, the thermal analysis of the designed chiral metasurface absorber further shows the large temperature difference between the left-handed and right-handed circularly polarized light. The demonstrated results can be utilized in various applications such as molecular detection, mid-infrared filter, thermal emission, and chiral imaging.
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Polaron absorption in aligned conjugated polymer films: breakdown of adiabatic treatments and going beyond the conventional mid-gap state model
This work resolves the inter- and intramolecular polarized absorption of polarons in the organic semiconductor P3HT, allowing previous theoretical predictions to be tested. Vibronic coupling is shown to be crucial in understanding polaron absorption.
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- Award ID(s):
- 2104234
- PAR ID:
- 10521898
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Materials Horizons
- Volume:
- 11
- Issue:
- 2
- ISSN:
- 2051-6347
- Page Range / eLocation ID:
- 545 to 553
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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