Stimuli-Responsive Complex Droplets and Polymeric Materials for Micro-optical Systems
Open Access
- Author:
- Goodling, Amy
- Graduate Program:
- Materials Science and Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 23, 2021
- Committee Members:
- Lauren Dell Zarzar, Dissertation Advisor/Co-Advisor
Lauren Dell Zarzar, Committee Chair/Co-Chair
James Hansell Adair, Committee Member
Tak Sing Wong, Committee Member
Zhiwen Liu, Outside Member
John C Mauro, Program Head/Chair - Keywords:
- soft materials
micro-optics
structural color
droplets
whispering gallery mode
microlenses
emulsions - Abstract:
- The field of micro-optical components has grown significantly in the past decades because of the ability to form light-weight, complex devices in a compact system. Using soft materials such as fluids or elastic polymers as the components of micro-optic devices allow for responsive multifunctional systems for a wide variety of applications ranging from optical communication, microlenses, optical tweezers, or beam steering. This thesis explores the dynamic tunability of soft materials for their use in micro-optical components. Through this experimentation, stimuli responsive materials provide a way to manipulate light in complex functionality while remaining simple in design. The focus of this work is to examine the use of biphasic complex microdroplets and polymeric materials for manipulating the properties of both white light and collimated laser light to study the structural coloration production, enhancement of lasing ability, and control of compound lensing spatial orientation. Microdroplets are dominated by interfacial reactions and their properties can therefore be tuned based on stimuli which affect this interfacial tension. Complex liquid droplets composed of two oil phases suspended in an aqueous medium give rise to light guiding fluid designs in which the morphology of the droplet liquid interfacial phases can dynamically control the incident light. In this work, complex liquid droplets are observed as a method of producing structural coloration in a fundamentally novel mechanism using micron lengths scales to create total internal reflection and subsequent interference of incident white light. This structural coloration mechanism was then explored in further detail by replicating the morphological design in solid polymeric films. Color-shifting images were shown to dynamically change with stimuli like temperature, UV light and mechanical force. Additionally, these complex droplets were studied with coherent light, wherein when one oil phase contained an absorbing dye and the droplets were subjected to coherent light, an enhancement of the light was observed in an effect through whispering gallery mode. Lastly the direction of light was manipulated using fluid lens optics coupled with a magnetic particle to control the direction of focused white light using a triaxial Helmholtz coils. Subsequently, this work provides a basis for fundamental exploration of complex liquid systems for stimuli-responsive and dynamic soft materials for application in a variety of micro-optical components.