2018 Physics/Theoretical Colloquium

Thursday, October 25th, 2018

3:45 – 4:45 p.m.

Rosen Auditorium (TA-53, Bldg. 1)

Refreshments at 3:15pm

 

Speaker:   Dr. Donald DiMarzio

Northrop Grumman

 

“Optical and RF Metamaterials at Northrup Grumman: Nanoparticle Self-Assembly for Quantum Dot Emission/Polarization Enhancement and Switchable/Modulated Transmission Lines for RF Reciprocity Control”

 

Abstract:  

Northrop Grumman Corporation’s NG Next Principal Scientist, Dr. Donald DiMarzio, will give a brief overview of the fundamental research conducted by Northrop Grumman’s Basic Research program, followed by a description of focused metamaterial efforts in DNA mediated nanoparticle self-assembly of photonic structures and transmission line based nonreciprocal systems.

 

DNA origami has revolutionized the field of nanoparticle self-assembly enabling a wide variety of nanostructures with applications in photonics and sensors. Here we demonstrate an innovative origami scaffold approach to metal and semiconductor nanoparticle assembly, and use it to assemble metal nanoantennas for polarized enhanced quantum dot (QD) excitation and emission control.  Precision nanoparticle positioning using DNA scaffolds results in good polarization control and excellent agreement between measured QD emission enhancement and theoretical predictions.  Such performance can have a significant impact on the development of practical single photon emitters and quantum photonic systems.

 

Transitioning from the optical realm, we have investigated RF metamaterial structures exhibiting dynamic tunability as well as directional reciprocity control.  This includes reconfigurable V-band metamaterials using split ring resonators and Schottky diodes fabricated by InP heterojunction bipolar transistor processing, and a generalized nonlinear transfer matrix approach to retrieve effective nonlinear metamaterial susceptibilities.  We have also begun the exploration of nonreciprocal metamaterials using time-space modulated nonlinear transmission lines employing a band gap engineering approach.  Such nonmagnetic nonreciprocal structures are expected to have a major impact in RF system applications.