Research
Professor Narayan’s group advances non-equilibrium materials synthesis and device integration. Foundational work spans ion implantation and laser annealing (supersaturated semiconductor alloys; ultra-shallow p–n junctions), discovery of pulsed-laser deposition (PLD) with tunable oxide alloys (e.g., VO₂, ZnMgO, ZnCdO), self-assembled magnetic nanodots, and recent discoveries of Q-carbon and Q-BN enabling direct conversion of carbon → diamond and h-BN → c-BN at ambient conditions.
U.S. patents on Q-carbon/BN/diamond devices
Reported properties include ultra-hardness, room-temperature ferromagnetism (RTFM), high-Tc superconductivity in B-doped Q-carbon, negative-electron-affinity field emission, electrochromism, heavy n/p doping beyond solubility limits, and NV-nanodiamond platforms for quantum technologies.
Research Thrusts
- Non-equilibrium laser processing & PLD
- Nanosecond laser melting/rapid quench; supersaturated alloys; ultra-shallow junctions; PLD growth of oxides with bandgap control (deep-UV → IR).
- Q-phases & direct conversions
- Q-carbon and Q-BN formation; carbon → diamond and h-BN → c-BN at room temperature/pressure; wafer-scale patterning.
- Domain Matching Epitaxy (DME)
- Epitaxial integration across large lattice misfit by matching integral plane multiples; nanolayers/dots/rods on practical substrates (e.g., Si(100)).
- Self-assembled magnetic nanodots
- 3D ordered arrays with substrate alignment; routes to spin-based device concepts.
- Defect engineering & RTFM
- Laser-introduced near-surface defects to tailor electrical/magnetic properties in oxides (ZnO, NiO, VO₂), perovskites (BiFeO₃), and topological oxides (Sr₃SnO).
- Devices & applications
- Nano-pocket LEDs, spin transistors, smart sensors, wear-resistant/field-emission coatings, quantum sensing/communication.
Signature Contributions & Highlights
- 1981 PRL: Transition-metal nanodots in ceramics (early bulk nanocrystalline route).
- Ion implantation & laser annealing: Supersaturated semiconductor alloys; laser-diffused ultra-shallow p–n junctions (solute trapping).
- Pulsed-laser deposition: Growth of VO₂, ZnMgO, ZnCdO with systematic bandgap tuning.
- Domain Matching Epitaxy: Paradigm for epitaxy across misfit scale; integration on Si(100); nano-pocket LED concept (quantum-confinement-enhanced IQE).
- Q-carbon / Q-BN: Ambient-condition conversion to diamond and c-BN; reported ultra-hardness, RTFM, high-Tc B-doped Q-carbon; NV nanodiamonds for quantum devices.
Funded Research Projects (selected)
| Project | Sponsor | Years |
|---|---|---|
| Direct Conversion of Carbon into Q-carbon and Diamond; Novel Nanostructures | NSF | 2017–2019 |
| Ultrafast Phase Transition & Structure–Property Correlations of Vanadium Oxide | NSF | 2014–2018 |
| Doping of Diamond & c-BN Beyond Solubility Limits for Solid-State Devices | ARO | 2017–2021 |
| Novel Epitaxial Vanadium Oxide Thin-Film Heterostructures | NSF | 2013–2019 |
| Topological Insulator Hybrid Structures for Optoelectronics | NSF | 2013–2018 |
| Q-carbon & Diamond Coatings on WC/Steel Cutting Tools | National Oilwell Varco | 2017–2018 |
| High-Efficiency Organic Solar Cells with Transparent Electrodes | NSF | 2007–2014 |
| Ultrafast Phase Transition in Vanadium Oxide | NSF | 2008–2014 |
| High-Efficiency Nanostructured LEDs on Nonpolar Substrates | NSF | 2008–2014 |
| III-Nitride & II-Oxide Heterostructures and Devices | ARO | 2014–2018 |
| Wafer Engineering of III-nitrides & ZnMgO Alloys | Kopin Corp. | 2007–2010 |
| Defect Engineering & DME in III-nitride Heterostructures | Veeco Corp. | 2011–2014 |
| Defect Engineering in Nanostructured Materials | NSF | 2011–2014 |
| TiN Nanowire Technology for Energy Harvesting | UNC-GA | 2017–2018 |
Domain Matching Epitaxy (DME) — At a Glance
Impact & Devices
- Opto/Power: Nano-pocket LEDs; high-efficiency III-nitride structures; band-engineered oxides.
- Spin/Quantum: RTFM oxides and Q-carbon; NV-nanodiamond platforms for sensing/communication.
- Coatings/Surfaces: Ultra-hard, adherent Q-carbon/diamond coatings; negative-electron-affinity emitters; electrochromic films.
- Integration: Wafer-scale patterning; epitaxy on Si(100); nanostructured layers/dots/rods for device prototyping.