A5030770813- Semiconductor Quantum Structures and Devices
- Nanowire Synthesis and Applications
- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Quantum Dots Synthesis And Properties
- GaN-based semiconductor devices and materials
- Semiconductor materials and interfaces
- Advanced Semiconductor Detectors and Materials
- ZnO doping and properties
- Integrated Circuits and Semiconductor Failure Analysis
- Electronic and Structural Properties of Oxides
- Ion-surface interactions and analysis
- Plasmonic and Surface Plasmon Research
- Silicon and Solar Cell Technologies
- Chalcogenide Semiconductor Thin Films
- Photonic Crystals and Applications
- Ga2O3 and related materials
- Quantum and electron transport phenomena
- Terahertz technology and applications
- Advanced Photonic Communication Systems
- Advanced Fiber Laser Technologies
- Metamaterials and Metasurfaces Applications
- Spectroscopy and Laser Applications
Australian National University
2016-2025
ARC Centre of Excellence for Transformative Meta-Optical Systems
2020-2025
Australian Research Council
2020-2024
ACT Government
2006-2023
Canberra (United Kingdom)
2014-2021
Institute of Electrical and Electronics Engineers
2014-2021
Canadian Standards Association
2013-2020
National Institute for Nanotechnology
2019-2020
Michigan State University
2019-2020
University of Canberra
2020
Abstract The recent rise of metamaterials opens new opportunities for absorbers due to their designed electrodynamic properties and effects, allowing the creation materials with effective values permittivity permeability that are not available in naturally occurring materials. Since first experimental demonstration 2008, literature has offered great advances metamaterial perfect (MMPAs) operating at frequencies from radio optical. Broadband indispensable thermophotovoltaics, photodetection,...
Controlling the crystallographic phase purity of III−V nanowires is notoriously difficult, yet this essential for future nanowire devices. Reported methods controlling require dopant addition, or a restricted choice diameter, and only rarely yield pure phase. Here we demonstrate that phase-perfect nanowires, arbitrary can be achieved simply by tailoring basic growth parameters: temperature V/III ratio. Phase without sacrificing important specifications diameter levels. Pure zinc blende free...
We have performed a comparative study of ultrafast charge carrier dynamics in range III–V nanowires using optical pump–terahertz probe spectroscopy. This versatile technique allows measurement important parameters for device applications, including lifetimes, surface recombination velocities, mobilities and donor doping levels. GaAs, InAs InP varying diameters were measured. For all samples, the electronic response was dominated by pronounced plasmon mode. Of three nanowire materials,...
The quest for nanoscale light sources with designer radiation patterns and polarization has motivated the development of nanoantennas that interact strongly incoming are able to transform its frequency, radiation, patterns. Here, we demonstrate dielectric AlGaAs efficient second harmonic generation, enabling control both directionality nonlinear emission. This is enabled by specialized III–V semiconductor nanofabrication high-quality nanostructures embedded in optically transparent low-index...
We report the growth of stacking-fault-free and taper-free wurtzite InP nanowires with diameters ranging from 80 to 600 nm using selective-area metal–organic vapor-phase epitaxy experimentally determine a quantum efficiency ∼50%, which is on par epilayers. also demonstrate room-temperature, photonic mode lasing these nanowires. Their excellent structural optical quality opens up new possibilities for both fundamental optics optoelectronic devices.
Crystalline silicon (c-Si) solar cells have been dominating the photovoltaic (PV) market for decades, and c-Si based photoelectrochemical (PEC) are regarded as one of most promising routes water splitting renewable production hydrogen. In this work, we demonstrate a nanoscale tantalum oxide (TaOx, ∼6 nm) an electron-selective heterocontact, simultaneously providing high-quality passivation to surface effective transport electrons either external circuit or water-splitting catalyst. The PV...
Selective area epitaxy (SAE) can be used to grow highly uniform III–V nanostructure arrays in a fully controllable way and is thus of great interest both basic science device applications. Here, an overview this promising technique presented, focusing on the growth fundamentals, formation nanowire arrays, monolithic integration silicon, heterostructures, networks various shapes. The applications these photonics, electronics, optoelectronics, quantum are also reviewed. Finally, current...
Abstract In recent years, III–V semiconductor nanowires have been widely investigated for infrared photodetector applications due to their direct and suitable bandgap, unique optical electrical properties, flexibility in device design create heterostructures, and/or grow on a foreign substrate such as Si with more effective strain relaxation compared planar structures. particular, vertically aligned ordered nanowire arrays emerged promising platform, since geometry‐related light absorption...
Abstract Diabetic ketoacidosis (DKA) is a life‐threatening acute complication of diabetes characterized by the accumulation ketone bodies in blood. Breath acetone, ketone, directly correlates with blood ketones. Therefore, monitoring breath acetone can significantly enhance safety and efficacy care. In this work, design fabrication an InP/Pt/chitosan nanowire array‐based chemiresistive sensor reported. By incorporation chitosan as surface‐functional layer Pt Schottky contact for efficient...
We demonstrate vertically aligned epitaxial GaAs nanowires of excellent crystallographic quality and optimal shape, grown by Au nanoparticle-catalyzed metalorganic chemical vapor deposition. This is achieved a two-temperature growth procedure, consisting brief initial high-temperature step followed prolonged at lower temperature. The essential for obtaining straight, on the (111)B substrate. temperature employed subsequent imparts superior nanowire morphology minimizing radial eliminating...
The stabilities of Pt/Ti bilayer metallizations in an oxidizing atmosphere have been investigated with several thicknesses interfacial Ti-bonding layers. Reactions the Pt/Ti/SiO2/Si interface were examined as a function various annealing conditions temperature range 200–800 °C by using Rutherford backscattering spectrometry, Auger electron spectroscopy, x-ray diffraction, and transmission microscopy. Thermal treatment oxygen was found to cause rapid oxidation Ti layer, accompanied migration...
Common II-VI compound semiconducting materials are stable thermodynamically with zincblende phase, while the II-O such as zinc oxide (ZnO) and beryllium (BeO) wurtzite cadmium (CdO) magnesium (MgO) in rocksalt phase. This phase disharmony same material family laid a challenge for basic physics practical applications optoelectronic devices, where ternary quaternary compounds employed. Thermodynamically ZnO is metastable which free from giant internal electric fields [001] directions has an...
Large energy shifts in the luminescence emission from strained InGaAs quantum dots are observed as a result of postgrowth annealing and also when raising upper cladding layer growth temperatures. These blueshifts occur concurrently with narrowing (from 61 to 24 meV) full width at half-maxima for dot ensemble. can be explained by interdiffusion or intermixing interfaces rather than strain effects due variations capping thickness. Temperature behavior annealed nonannealed samples indicates...
We study the evolution of lattice defects in single-crystal ZnO bombarded with 60-keV ${}^{28}\mathrm{Si}$ and 300-keV ${}^{197}\mathrm{Au}$ ions at 77 300 K. To characterize ion-beam-produced structural defects, we use a combination Rutherford backscattering/channeling (RBS/C) spectrometry, cross-sectional transmission electron microscopy (XTEM), x-ray photoelectron spectroscopy, atomic force microscopy. Results show that exhibits strong dynamic annealing, even high-dose bombardment heavy...
The deformation behavior of bulk ZnO single crystals is studied by a combination spherical nanoindentation and atomic force microscopy. Results show that exhibits plastic for relatively low loads (≳4–13 mN with an ∼4.2 μm radius indenter). Interestingly, the elastic–plastic transition threshold depends on loading rate, faster resulting, average, in larger values. Multiple discontinuities (so called “pop-in” events) force–displacement curves are observed during indentation loading. No...
We have used transient terahertz photoconductivity measurements to assess the efficacy of two-temperature growth and core-shell encapsulation techniques on electronic properties GaAs nanowires. demonstrate that core leads an almost doubling in charge-carrier mobility a tripling carrier lifetime. In addition, overcoating with larger-bandgap material is shown reduce density surface traps by 82%, thereby enhancing charge conductivity.
III-V compound semiconductors (SC) have played a crucial role in the development of optoelectronic devices for broad range applications. Major applications InP or GaAs based SC are optical fiber communications, infrared and visible LEDs/LDs high efficiency solar cells. GaN compounds extremely important short wavelength light emitters used solid state lighting systems. We review device various materials.
We have synthesized ternary InGaAs nanowires on (111)B GaAs surfaces by metal−organic chemical vapor deposition. Au colloidal nanoparticles were employed to catalyze nanowire growth. observed the strong influence of density height, tapering, and base shape specific with high In composition. This dependency was attributed large difference diffusion length between Ga reaction species, being more mobile species. Energy dispersive X-ray spectroscopy analysis together high-resolution electron...
We use polarization-resolved and temperature-dependent photoluminescence of single zincblende (ZB) (cubic) wurtzite (WZ) (hexagonal) InP nanowires to probe differences in selection rules bandgaps between these two semiconductor nanostructures. The WZ exhibit a bandgap 80meV higher energy than the ZB nanowires. temperature dependence PL is similar but not identical for find that strong polarization parallel nanowire axis, while polarized emission perpendicular axis. This behavior interpreted...