Poling induced mass transport in thin polymer films

Area of Science:

• Materials Science
• Polymer Science
• Nonlinear Optics

Background:

• Nonlinear optical (NLO) materials are crucial for advanced optical technologies.
• Fabrication of NLO-active polymer films requires precise control over material morphology.
• Corona poling is a common technique for inducing NLO properties in polymers.

Purpose of the Study:

• To investigate polymer film morphology modifications during corona poling.
• To understand the factors influencing surface and spatial inhomogeneities.
• To optimize poling conditions for enhanced NLO properties.

Main Methods:

• Corona poling of polymer films.
• Optical, second harmonic generation (SHG), and scanning electron microscopy (SEM) measurements.
• Electrical conductivity measurements of thin films.

Main Results:

• Surface and spatial inhomogeneities form in polymer films under specific corona poling conditions.
• The density of inhomogeneities depends on poling field strength, temperature, and prepoling conditions.
• Optimized poling conditions, avoiding surface modifications, increased effective nonlinearity up to 10 times.

Conclusions:

• Controlling corona poling parameters is essential for fabricating high-performance NLO polymer films.
• Minimizing structural inhomogeneities leads to significantly enhanced nonlinear optical responses.
• The study provides insights into the formation mechanisms of these inhomogeneities, guiding future material design.