Cottrell Scholar Awards - 2016
Exploring the Interplay between Nanoscale Design and Optical Properties of Materials: A Research and Educational Approach
Currently, many researchers are investigating nanoscale physics, the interplay of matter and energy at incredibly tiny scales – a nanometer is one-billionth of a meter. That’s because surprising, technologically useful, and just flat-out amazing physical phenomena occur at the nanoscale.
Maiken H. Mikkelsen, assistant professor of physics at Duke University, is attempting to design and chemically construct new nanoscale materials with unusual, exciting optical properties. She aims to work with composite material structures consisting of components of only 10 nanometers, or about the size of 20 silicon atoms.
Specifically, she and her research associates will focus on light-matter interactions in novel semiconductor nanostructures manufactured in the Duke clean room. The term “semiconductor” refers to a material with atoms arranged in a crystalline-lattice structure exhibiting technologically useful properties such as passing current more easily in one direction than the other.
Mikkelsen will explore how traditional semiconductors can be made to behave in new ways by embedding them in precisely designed nanoscale structures, effectively creating new composite materials with tailored properties. The approach involves trapping and squeezing light into nanometer-sized gaps between a metal nanocube and a metal surface, a structure she calls a “nanopatch antenna.” Semiconductors placed in this gap are energized by the intensified light, causing them to emit light more than 1,000 times faster, with higher efficiency, and in the desired directions. The intensified light produced in the nanopatch antenna is so energetic that scientists describe it as a “quantum plasma oscillation,” which, in their calculations, they treat more or less as they would other subatomic particles. Thus, they call these plasma oscillations “quasiparticles.”
“This process,” Mikkelsen said, “enables novel optical properties to occur which are vastly different from naturally occurring materials. Building upon this allows for a new class of hybrid materials to be created with finely tuned optical properties.” Her work could one day lead to more efficient LED bulbs, better TVs and more efficient solar-electric power.
For the education component of the Cottrell Scholar Award, Mikkelsen aims to create new and interactive teaching techniques in undergraduate courses to enhance diversity in physics, and through these initiatives to address the shrinking pipeline of students choosing careers in the sciences.
“I will create opportunities for undergraduate students to develop creative and independent thinking through a new interactive undergraduate course on ‘Physics of Semiconductor Nanostructures,’ new modules for the introductory Quantum Mechanics course, and independent research opportunities,” she said.