In this talk, I will first discuss the Air Force Research Laboratory (AFRL) strategy for investment in quantum information research, highlighting activities in the Information (Rome, NY), Space Vehicles and Directed Energy (Albuquerque, NM) and Materials and Manufacturing and Sensors Directorates (Dayton, OH). In the near term, AFRL is pursuing quantum sensing technologies for improved timekeeping and navigation in GPS denied environments. Mid-term investments are focused in architectures for quantum networks, including the entangled photon sources and quantum memories needed to realize them. Far-term investments are focused on exploiting novel quantum algorithms for Air Force relevant problems such as machine learning, optimization, and materials discovery.
In the second part of my talk, I will provide an overview of my group’s efforts in the modeling, synthesis, and nano-positioning of point defects in semiconductor nanocrystals. We have used ab initio quantum chemistry (supercell) calculations to model the photoluminescence of a new vanadium-nitrogen defect in diamond. Using ion implantation, we have attempted to synthesize this defect, and I will present spectroscopy data for it. To improve the reliable coupling of defect centers to quantum photonic devices, we desire nanoscale positioning of defects in diamond. Toward this end, we have built a chemical vapor deposition reactor to introduce functionalized seed molecules during diamond synthesis. We have demonstrated diamond nanoparticle growth with very low graphite content. I will also present a highly scalable optothermal printing method for removing nanoparticles from a donor substrate and placing them on a target substrate, such as a photonic crystal cavity.
Finally, I will discuss a liquid phase exfoliation (LPE) method for deterministically producing single-photon emitting defects in 2D transition metal dichalcogenides (TMDs). In contrast to mechanical exfoliation, LPE produces 2D TMDs with relatively few defects. This allows the subsequent addition of atomistic defects to spatially and optically tailor the single-photon emission. We plan to explore a large library of 2D TMDs to uncover excitonic physics associated with single-photon emission and optimize the emitter brightness.