Nanoscience

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Nanoscience Materials and Photonics Research
Research School of Physical Sciences and
Engineering
www.rsphysse.anu.edu.au
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Research at RSPSE
Communications and IT
Chemical physics
Theory
Bioscience
Experimental Nuclear Physics
Plasma physics
Atomic and molecular physics
Materials Science
Photonics
Laser physics
Nanotechnology
Electronic Materials
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Materials, Nanoscience and Photonics in RSPSE

• Complex mesoporous and nano-materials
• Laser ablation
• Novel thin films and nanotubes
• Photonics polymer optics and quantum laser
  devices
• Nanoparticles for optoelectronics and
  biomedical
• Nanoindentation and phase changes in silicon

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Micro-computed tomography
Mark Knackstedt et al

• Fundamental understanding of disordered and
  porous materials
• Predicting properties via imaging,
  visualisation, theoretical and computational
  modelling.

Nanoscience merges with the mesoscale through
topics such as

• Oil and gas recovery
• Ground water salinity
• Biomedical engineering
• microfluidics
• Granular materials processing
• Paper printing technologies

Simulated fluid velocity maps in coral 0.5 mm
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Nanoparticlates for Biomedical applications
Tim Senden et al
Liquid mercury Encapsulate (250nm)
Radiolabelled Nanoparticulate Composites
Aerosol, aqueous dispersion or emulsion
Many other isotopes encapsulated Thallium Berylli
um Copper Zinc Holmium Yttrium Sodium a-iron And
others.
Relative size g-Globulin
Fibrinogen
Empty shell without mercury
FibrinLite - diagnostic imaging of blood clots

• Animal studies complete and pre-Phase 1 clinical
  trial performed.
• Company will soon spin-off from University.

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National Positron Beamline Facility
Stephen Buckman et al
Materials
Nano-structured materials Semiconductors,
polymers, low dielectric materials
(porosity) Positron Annihilation Lifetime
Spectroscopy (PALS)
AMO
Voids and pores in materials at the nanoscale
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Laser Ablation Ultrafast Lasers
Andre Rode et al
Diamond-Like Carbon Nano-Foam

• Laser ablation of Graphite in Ar gas
• Cluster assembled a-carbon nanofoam made of 6-9
  nm clusters
• Bulk density 2-20 mg/cm3
• Resistivity 3109 Ohmcm
• Surface area 300-400 m2/g
• A fractal ordering at (0.1-1.0) µm scale
• Density of unpaired spins 1.7?1020 g-1 (1 per
  300 C-atoms)
• A novel hyperbolic structure with 5.60.5 Å
  length scale

• Mode-Locked Antares NdYAG plus amplifier
• Fixed 76 MHz repetition rate of 60 ps pulses
• 0.3 µJ 25 W 109 W/cm2
• Home-made NdYVO4 laser amplifier

• Continuous vapour flow
• Extra degree of freedom via duty cycle
• Efficient evaporation - no time for the heat
  wave
• Total atomisation

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Boron nitride nanotubes
Ying Chen et al
Boron nitride from boron milled in NH3 and
annealed at gt1000oC

• Bamboo tubes

• Single and multiwalled tubes

Growth process entirely in the solid phase via
ball milling
20 nm
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Silicon nanocrystals imbedded in SiO2
Rob Elliman et al
Silicon
silicon nanocrystal
Oxygen
silicon nanocrystal
ion source
Glass SiO2
Colour of light varies with size
silicon ions
Ion implantation
heating
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Polymer optics inorganic polymer-glass
waveguides and optical splitters
Barry Luther-Davies et al
Metallise
Spin on upper cladding and UV expose
Pattern transfer to metal
Wet development
Wet development
Wafer diced to make chip
Pattern transfer By UV exposure
Spin on lower cladding and UV expose
Spin on core
Si Wafer
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Typical Guides
Waveguide core

• MMI splitter output

Simple, cheap process, can tailor properties RPO
spin-off company
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Quantum well, wire and dot lasers
C. Jagadish et al
laser
1000 nm
Laser array
1000 nm
laser wire structure
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Quantum Well Intermixing
Different Bandgaps on the same chip

• Diffusion of In and Ga across interface creates
  graded region in the case of GaAs/InGaAs Quantum
  Wells
• Changes Bandgap, refractive index, absorption
  coefficient

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Quantum computing architecture
Neil Manson Matt Sellers

• Atoms or ions in crystals can be used to store
  information (no fabrication)
• Each can be addressed by optical
• absorption frequency
• All the computing operations are performed
  optically with pulse of light

Demonstration of quantum computing gate
Distances nm
Requires development of specialised lasers
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Nanoindentation and phase transformations in
silicon A new memory technology?
Jodie Bradby et al
Phases of Si during indentation
Si-II
Metallic b-Sn
a-Si
Amorphous
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XTEM of Indents in amorphous Si
as-implanted
unannealed

• Annealed a-Si behaves
• like crystalline Si

annealed