Research

Professor Narayan started nanoscience revolution in bulk nanocrystalline material in1981 with his seminal paper in Physical Review Letters on transition-metal nanodots in ceramics. His fundamental discoveries in ion implantation and laser annealing led to novel supersaturated semiconductor alloys and laser-diffused ultra-shallow p-n junctions via solute trapping phenomena. His laser annealing research led to the discovery of pulsed laser deposition and formation of new materials such as VO2, ZnMgO, and ZnCdO alloys, where bandgap can be varied systematically from deep ultraviolet to infrared. His recent work has focused on three-dimensional self-assembly of magnetic nanodots, where each dot is aligned with respect to the substrate. This research was hailed by NSF as the significant discovery of the year 2004. His recent research has focussed on the discovery of Q-carbon and Q-BN conversion of carbon into diamond and h-BN into c-BN. These materials have unprecedented properties, including hardness (greater than diamond), ferromagnetism on Q-carbon, high-temperature superconductivity in B-doped Q-carbon, high field emission through negative electron affinity, electrochromic effect in Q-carbon, n- and p-type doping beyond retrograde solubility limit, NV nanodiamonds for atomic sensing and quantum computing and related novel solid-state devices.

Funded Research Projects

  • Direct Conversion of Carbon into Q-carbon and Diamond and Fabrication of Novel Nanostructures: NSF (2017-2019)
  • Ultrafast phase transition and critical issues in structure-property correlations of vanadium oxide: NSF (2014-2018)
  • Doping of Diamond and c-BN beyond Thermodynamic Solubility Limit for Solid State Devices: ARO (2017-2021)
  • Novel Epitaxial Vanadium Oxide Thin Film Heterostructures: NSF (2013-2019)
  • Topological Insulator Hybrid Structures for Novel Optoelectronic Applications: NSF (2013-2018)
  • Q-carbon and Diamond Coatings on WC and Steel Cutting Tools: National Oilwell Varco (2017-2018)
  • High Efficiency Organic Solar Cells with Novel Transparent Electrodes: NSF (2007-2014)
  • Ultrafast phase transition and critical issues in structure-property correlations of vanadium oxide: NSF (2008-2014)
  • High Efficiency Nanostructured Light Emitting Diodes on Nonpolar Substrates: NSF (2008-2014)
  • III-Nitride and II-Oxide Based Heterostructures and Devices : Army Research Office (2014-2018)
  • Wafer Engineering of III-nitrides and ZnMgO Alloys: Kopin Corporation (2007-2010)
  • Defect Engineering and Domain Epitaxy in III-nitride Heterostructures: Veeco Corporation (2011-2014)
  • Defect Engineering in Nanostructured Materials: NSF (2011-2014)
  • TiN Nanowire based Technology for Energy Harvesting: UNC-GA (2017-2018)

His invention of domain matching epitaxy across the misfit scale has revolutionized epitaxial integration of nanostructured materials in the form of nanolayers, nanodots, and nanorods on practical substrates such as silicon(100). The DME paradigm has led to the integration of exciting new materials, which include perovskites such as NdNiO3, vanadium oxide, titanium oxide, nickel oxide, and most recent novel topological insulator (Sr3SnO) and bismuth ferrite with unique magnetic properties (Nano Lett. 2013). The DME paradigm involves the matching of integral multiples of lattice planes across the film-substrate interface, where misfit across the scale can be accommodated via the principle of domain variation. All III-nitrides LEDs, lasers and high-power devices with lattice misfit over 15% are grown by DME paradigm on silicon and sapphire substrates. Narayan also invented nanostructured (Nano Pocket) LEDs, where internal quantum efficiency is considerably enhanced through quantum confinement of carriers via thickness variation. This process is adopted universally for manufacturing high-efficiency LEDs. His recent seminal contributions have focused on the controlled introduction of defects by pulsed laser irradiation to modify electrical and magnetic properties of near-surface nanolayers. The RTFM (room-temperature ferromagnetism) can be introduced in materials such as ZnO, NiO, VO2, Sr3SnO, BiFeO3 and BiTiO3 to further enhance their functionality. By introducing RTFM into the heterostructures of these materials, he has opened a new frontier of solid state devices with novel and smart functionalities ranging from spin transistors to smart sensors on a chip. His discoveries of Q-carbon and diamond-related materials with extraordinary properties have opened a new frontier in materials science and engineering.