CD Imaging at High Spatial Resolution at Diamond B23 Beamline: Evolution and Applications.

Area of Science:

• Optics and Photonics
• Materials Science
• Spectroscopy

Background:

• Circular Dichroism (CD) imaging is crucial for studying chiral materials.
• Analyzing supramolecular structures in thin films requires advanced techniques.
• Previous methods were limited by optical artifacts like birefringence.

Purpose of the Study:

• To introduce and validate an expanded CD imaging facility with Mueller Matrix Polarimetry (MMP).
• To investigate the homogeneity of supramolecular structures in chiral thin films.
• To establish critical parameters for reproducible thin film preparation.

Main Methods:

• Utilized a highly collimated microbeam at the Diamond Light Source B23 beamline for CD imaging (190-650 nm).
• Integrated a Mueller Matrix Polarimeter (MMP) to evaluate circular birefringence, linear dichroism, and linear birefringence.
• Prepared thin chiral films using various methods (drop casting, spin coating, spraying) at different conditions.

Main Results:

• Demonstrated the capability of CD imaging and MMP to characterize chiroptical properties of thin films.
• Preliminary data from the MMP system will be presented.
• Identified the influence of preparation conditions on film homogeneity.

Conclusions:

• The combined CD imaging and MMP technique allows for comprehensive analysis of chiral thin films.
• This characterization is essential for achieving reproducible and uniform specimen preparation.
• The findings have significant implications for optoelectronic materials, biosensors, and biological tissue analysis.