At the nanoscale, unique properties and phenomena emerge that can lead to scientific and technological paradigms beyond those classically envisioned. Exploring these opportunities at the few-nanometer regime requires unprecedented precision, resolution and control, not readily feasible through conventional techniques. In particular, the dynamic, reliable and reversible structural tuning of such small dimensions is a great challenge, yet a promising platform to enable nanosystems of new and improved functionalities.
Here, I will introduce an approach to achieve nanometer precision, resolution and control in fabrication and tunability by engineering surfaces and surface adhesive forces. In this scheme, molecular layers are utilized as nanoscale springs in which conformational changes in response to external stimuli allow controlled and reversible tuning of the architecture. I will discuss the use of this mechanism in developing tunneling-based nanoelectromechanical switches in which the switching gap is composed of an electromechanically tunable metal-molecule-metal tunneling junction. With potential to achieve stiction-free and low-voltage operation, these devices address two of the main challenges commonly faced by electromechanical switches. Moreover, in these molecular junctions, conformational changes can lead to modulation of light-matter interactions. Utilizing this principle, I will introduce a plasmonic ruler as a much desired metrology tool to study motion and mechanical properties at the nanoscale.
The techniques developed for precise and controlled nanoscale fabrication and tunability extend in applications beyond the device platforms discussed here. I will conclude by providing an overview of these possibilities and sharing my vision for engineering at the limits of the nanoscale.
Farnaz Niroui is a Ph.D. candidate in the Department of Electrical Engineering and Computer Science at Massachusetts Institute of Technology where she works with Professors Vladimir Bulović and Jeffrey Lang. She received her Master of Science degree in Electrical Engineering from MIT in 2013 and completed her undergraduate studies in Nanotechnology Engineering at University of Waterloo in 2011. Her research interest lies at the interface of device physics, nanofabrication, and materials science to study, manipulate and engineer devices and systems with unique functionalities at the nanoscale. Farnaz is a recipient of the Natural Sciences and Engineering Research Council of Canada Scholarship for graduate studies and the Miller Fellowship, and has been selected to the Rising Stars in EECS program in 2015 and 2016.