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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
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Temperature-dependent circular conversion dichroism from chiral metasurfaces patterned in Dirac semimetal Cd3As2
Guangyi Jia1, Zhenxian Huang1, Yan Zhou1
1School of Science, Tianjin University of Commerce, Tianjin 300134, P. R. China. wanghw@tjcu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|June 2, 2021
Summary
This study designs chiral metasurfaces from Cd3As2, investigating temperature effects on circular polarization differential transmittance (CPDT). Lower temperatures enhance CPDT, with potential for significant differential transmittance at 80 K.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanophotonics
Background:
- Chiral metasurfaces offer unique light manipulation properties.
- Dirac semimetals like Cd3As2 exhibit tunable electronic and optical characteristics.
- Understanding temperature-dependent optical responses is crucial for device applications.
Purpose of the Study:
- To design and investigate chiral metasurfaces based on Cd3As2.
- To analyze the temperature dependence of circular conversion dichroism (CPDT).
- To explore the influence of structural parameters and incident angles on CPDT.
Main Methods:
- Design of chiral metasurfaces with L-shaped holes in Cd3As2 thin films.
- Rigorous coupled-wave analysis (RCWA) for optical simulations.
- Systematic study of temperature, wavelength, thickness, and angle variations.
Main Results:
- Decreasing temperature leads to narrower CPDT peaks and dips, reaching a maximum differential transmittance above 0.60 at 80 K.
- CPDT peak and dip values show 'Z' and 'S' type variations with increasing temperature, saturating above 500 K.
- CPDT extremum positions exhibit blueshift/redshift tendencies with temperature changes depending on wavelength.
Conclusions:
- Temperature is a critical factor in tuning the CPDT of Cd3As2 chiral metasurfaces.
- Optimized structural and environmental parameters can enhance optical functionalities.
- The derived formulae provide predictive insights into CPDT behavior across a wide temperature range.
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