@article {235111, title = {Deterministic coupling of delta-doped nitrogen vacancy centers to a nanobeam photonic crystal cavity}, journal = {Applied Physics Letters}, volume = {105}, number = {26}, year = {2014}, abstract = {The negatively charged nitrogen vacancy center (NV) in\ diamond\ has generated significant interest as a platform for quantum information processing and sensing in the solid state. For most applications, high quality\ optical cavities\ are required to enhance the NV zero-phonon line (ZPL) emission. An outstanding challenge in maximizing the degree of NV-cavity coupling is the deterministic placement of NVs within the\ cavity.\ Here, we report\ photonic crystal\ nanobeamcavities\ coupled to NVs incorporated by a delta-doping technique that allows nanometer-scale vertical positioning of the emitters. We demonstrate\ cavities\ with Q up to \~{}24 000 and mode volume V \~{} 0.47(λ/n)3\ as well as\ resonant\ enhancement of the ZPL of an NV ensemble with Purcell factor of \~{}20. Our\ fabrication\ technique provides a first step towards deterministic NV-cavity coupling using spatial control of the emitters.}, url = {http://dx.doi.org/10.1063/1.4904909}, author = {Lee, Jonathan C. and Bracher, David O. and Cui, Shanying and Ohno, Kenichi and McLellan, Claire A. and Zhang, Xingyu and Andrich, Paolo and Alem{\'a}n, Benjamin and Russell, Kasey J. and Magyar, Andrew P. and Aharonovich, Igor and Bleszynski Jayich, Ania and Awschalom, David and Hu, Evelyn L.} } @article {199571, title = {Distinctive signature of indium gallium nitride quantum dot lasing in microdisk cavities}, journal = {Proceedings of the National Academy of Sciences}, year = {2014}, url = {http://www.pnas.org/content/early/2014/08/27/1415464111.abstract}, author = {Woolf, Alexander and Puchtler, Tim and Aharonovich, Igor and Tongtong Zhu and Niu, Nan and Wang, Danqing and Oliver, Rachel and Hu, Evelyn L.} } @article {161516, title = {Silicon-Vacancy Color Centers in Nanodiamonds: Cathodoluminescence Imaging Markers in the Near Infrared}, journal = {Small}, volume = {DOI: 10.1002/smll.201303582}, year = {2014}, abstract = {Nanodiamonds doped with silicon-vacancy (Si-V) color centers are shown to be a promising candidate for cathodoluminescence (CL) imaging at the nanoscale, providing bright, non-bleaching, narrow-linewidth emission at wavelengths within the near-IR window of biological tissue. CL emission intensity from negative charge-state Si-V centers is greatly enhanced by increasing the nitrogen concentration during nanodiamond growth.}, author = {Huiliang Zhang and Aharonovich, Igor and David R. Glenn and Richard Schalek and Magyar, Andrew P. and Lichtman, Jeff W and Hu, Evelyn L. and Walsworth, Ronald L.} } @article {161506, title = {The structure{\textendash}function relationships of a natural nanoscale photonic device in cuttlefish chromatophores}, journal = {Journal of The Royal Society Interface}, volume = {11}, number = {93}, year = {2014}, abstract = {Cuttlefish, Sepia officinalis, possess neurally controlled, pigmented chromatophore organs that allow rapid changes in skin patterning and coloration in response to visual cues. This process of adaptive coloration is enabled by the 500\% change in chromatophore surface area during actuation. We report two adaptations that help to explain how colour intensity is maintained in a fully expanded chromatophore when the pigment granules are distributed maximally: (i) pigment layers as thin as three granules that maintain optical effectiveness and (ii) the presence of high-refractive-index proteins{\textemdash}reflectin and crystallin{\textemdash}in granules. The latter discovery, combined with our finding that isolated chromatophore pigment granules fluoresce between 650 and 720 nm, refutes the prevailing hypothesis that cephalopod chromatophores are exclusively pigmentary organs composed solely of ommochromes. Perturbations to granular architecture alter optical properties, illustrating a role for nanostructure in the agile, optical responses of chromatophores. Our results suggest that cephalopod chromatophore pigment granules are more complex than homogeneous clusters of chromogenic pigments. They are luminescent protein nanostructures that facilitate the rapid and sophisticated changes exhibited in dermal pigmentation. }, author = {Leila F. Deravi and Magyar, Andrew P. and Sean P. Sheehy and George R.R. Bell and Lydia M. Mathger and Stephen L. Senft and Trevor J. Wardill and William S. Lane and Alan M. Kuzirian and Roger T. Hanlon and Hu, Evelyn L. and Kevin Kit Parker} } @article {159471, title = {Constrained, aqueous growth of three-dimensional single crystalline zinc oxide structures}, journal = {Applied Physics Letters Materials}, volume = {2}, year = {2014}, pages = {012111}, abstract = {We study low temperature (90 {\textdegree}C) aqueous growth of single crystal zinc oxide structures through patterned PMMA molds of different sizes, shapes, and orientations. We demonstrate the ability to create 3D shapes with smooth vertical sidewalls. Although the unconstrained growth is influenced by the hexagonal geometry of the underlying crystal structure, the ZnO is shown to conform exactly to any shape patterned. Using electron backscatter diffraction and scanning electron microscopy we show that the mold orientation, in conjunction with control of the growth rates of the c and m planes of the ZnO, is crucial in determining the final structure shape.}, url = {http://dx.doi.org/10.1063/1.4863075}, author = {Kathryn J. Pooley and Joo, John H. and Hu, Evelyn L.} } @article {159446, title = {Synthesis of luminescent europium defects in diamond}, journal = {Nature Communications}, volume = {5}, year = {2014}, pages = {3523}, abstract = {Lanthanides are vital components in lighting, imaging technologies and future quantum memory applications owing to their narrow optical transitions and long spin coherence times. Recently, diamond has become a pre-eminent platform for the realisation of many experiments in quantum information science. Here we demonstrate a promising approach to incorporate Eu ions into diamond, providing a means to harness the exceptional characteristics of both lanthanides and diamond in a single material. Polyelectrolytes are used to electrostatically assemble Eu(III) chelate molecules on diamond and subsequently chemical vapour deposition is employed for the diamond growth. Fluorescence measurements show that the Eu atoms retain the characteristic optical signature of Eu(III) upon incorporation into the diamond lattice. Computational modelling supports the experimental findings, corroborating that Eu(III) in diamond is a stable configuration. The formed defects demonstrate the outstanding chemical control over the incorporation of impurities into diamond enabled by the electrostatic assembly together with chemical vapour deposition growth.}, author = {Magyar, Andrew and Hu, Wenhao and Shanley, Toby and Flatte, Michael E. and Hu, Evelyn and Aharonovich, Igor} } @article {159441, title = {High quality SiC microdisk resonators fabricated from monolithic epilayer wafers}, journal = {Applied Physics Letters}, volume = {104}, year = {2014}, pages = {051109}, abstract = {The exquisite mechanical properties of SiC have made it an important industrial material with applications in microelectromechanical devices and high power electronics. Recently, the optical properties of SiC have garnered attention for applications in photonics, quantum information, and spintronics. This work demonstrates the fabrication of microdisks formed from a p-N SiC epilayer material. The microdisk cavities fabricated from the SiC epilayer material exhibit quality factors of as high as 9200 and the approach is easily adaptable to the fabrication of SiC-based photonic crystals and other photonic and optomechanical devices.}, author = {Magyar, Andrew P. and Bracher, David and Lee, Jonathan C. and Aharonovich, Igor and Hu, Evelyn L.} } @article {159436, title = {Two-dimensional hybrid photonic/plasmonic crystal cavities}, journal = {Optics Express}, volume = {22}, number = {7}, year = {2014}, pages = {8219-8225}, abstract = {We present a 2-D plasmonic crystal design with visible band-gap by combining a 2-D photonic crystal with TM band-gap and a silver surface. Simulations show that the presence of the silver surface gives rise to an expanded band-gap. A plasmonic crystal defect cavity with Q ~300 and mode volume ~1.9x10-2 (λ/n) 3 can be formed using our design. The total Q of such a cavity is determined by both the radiative loss of the dielectric component, as well as absorption loss to the metal. We provide design criteria for the optimization of the total Q to allow high radiative or extraction efficiency.}, author = {Liu, Tsung-Li and Russell, Kasey J. and Cui, Shanying and Hu, Evelyn L.} }