Terahertz Emission from 
Bismuth
 Thin Films Induced by Excitation with Circularly Polarized Light

Here, we report the formation of homochiral supramolecular thin film from achiral molecules, by using circularly polarized light (CPL) only as a chiral source, on the condition that irradiation of CPL does not induce a photochemical change of the achiral molecules. Thin films of self-assembled structures consisting of chiral supramolecular fibrils was obtained from the triarylamine derivatives through evaporation of the self-assembled triarylamine solution. The homochiral supramolecular helices with the desired handedness was achieved by irradiation of circularly polarized visible light during the self-assembly process, and the chiral stability of supramolecular self-assembled product was achieved by photopolymerization of the diacetylene moieties at side chains of the building blocks, with irradiation of circularly polarized ultraviolet light. This work provides a novel methodology for the generation of homochiral supramolecular thin film from the corresponding achiral molecules.

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Three-Way-Switchable ( Right/ Left/ OFF) Selective Reflection of Circularly Polarized Light on Solid Thin Films of Helical Polymer Blends

Angewandte Chemie ◽

10.1002/ange.201602035 ◽

2016 ◽

Vol 128 (25) ◽

pp. 7242-7246 ◽

Cited By ~ 8

Author(s):

Yuuya Nagata ◽

Makoto Uno ◽

Michinori Suginome

Keyword(s):

Thin Films ◽

Polymer Blends ◽

Polarized Light ◽

Selective Reflection ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Helical Polymer ◽

Solid Thin Films

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Anomalous circular bulk photovoltaic effect in BiFeO3 thin films with stripe-domain pattern

Nature Communications ◽

10.1038/s41467-020-20446-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

David S. Knoche ◽

Matthias Steimecke ◽

Yeseul Yun ◽

Lutz Mühlenbein ◽

Akash Bhatnagar

Keyword(s):

Thin Films ◽

Large Scale ◽

Photovoltaic Effect ◽

Specific Interaction ◽

Polarized Light ◽

Open Circuit ◽

Domain Pattern ◽

Stripe Domain ◽

Circularly Polarized Light ◽

Circularly Polarized

AbstractMultiferroic bismuth ferrite, BiFeO3, offers a vast landscape to study the interplay between different ferrroic orders. Another aspect which is equally exciting, and yet underutilized, is the possibility of large-scale ordering of domains. Along with symmetry-driven bulk photovoltaic effect, BiFeO3 presents opportunities to conceptualize novel light-based devices. In this work, we investigate the evolution of the bulk photovoltaic effect in BiFeO3 thin films with stripe-domain pattern as the polarization of light is modulated from linear to elliptical to circular. The open-circuit voltages under circularly polarized light exceed ± 25 V. The anomalous character of the effect arises from the contradiction with the analytical assessment involving tensorial analysis. The assessment highlights the need for a domain-specific interaction of light which is further analyzed with spatially-resolved Raman measurements. Appropriate positioning of electrodes allows observation of a switch-like photovoltaic effect, i.e., ON and OFF state, by changing the helicity of circularly polarized light.

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Differential polarization imaging of sickled cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102390 ◽

1988 ◽

Vol 46 ◽

pp. 62-63

Author(s):

Marcos F. Maestre

Keyword(s):

Optical Properties ◽

Theoretical Approach ◽

Polarized Light ◽

Polarization Microscopy ◽

Spectroscopic Techniques ◽

Polarization Imaging ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Microscopic Scale ◽

Chiral Structures

Recently we have developed a form of polarization microscopy that forms images using optical properties that have previously been limited to macroscopic samples. This has given us a new window into the distribution of structure on a microscopic scale. We have coined the name differential polarization microscopy to identify the images obtained that are due to certain polarization dependent effects. Differential polarization microscopy has its origins in various spectroscopic techniques that have been used to study longer range structures in solution as well as solids. The differential scattering of circularly polarized light has been shown to be dependent on the long range chiral order, both theoretically and experimentally. The same theoretical approach was used to show that images due to differential scattering of circularly polarized light will give images dependent on chiral structures. With large helices (greater than the wavelength of light) the pitch and radius of the helix could be measured directly from these images.

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