a nuclear spin quantum computer in silicon n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
A NUCLEAR SPIN QUANTUM COMPUTER IN SILICON PowerPoint Presentation
Download Presentation
A NUCLEAR SPIN QUANTUM COMPUTER IN SILICON

Loading in 2 Seconds...

play fullscreen
1 / 18

A NUCLEAR SPIN QUANTUM COMPUTER IN SILICON - PowerPoint PPT Presentation


  • 69 Views
  • Uploaded on

M A R C. Microanalytical Research Centre. A NUCLEAR SPIN QUANTUM COMPUTER IN SILICON. National Nanofabrication Laboratory, School of Physics, University of New South Wales Laser Physics Centre, Department of Physics, University of Queensland

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'A NUCLEAR SPIN QUANTUM COMPUTER IN SILICON' - rosina


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
a nuclear spin quantum computer in silicon

M A R C

Microanalytical Research Centre

A NUCLEAR SPINQUANTUM COMPUTERIN SILICON
  • National Nanofabrication Laboratory, School of Physics, University of New South Wales
  • Laser Physics Centre, Department of Physics, University of Queensland
  • Microanalytical Research Centre, School of Physics, University of Melbourne
key personnel
Students

Paul Otsuka

MatthewNorman

Elizabeth Trajkov

Brett Johnson

Amelia Liu*

Leigh Morpheth

David Hoxley*

Andrew Bettiol

Deborah Beckman

Jacinta Den Besten

Kristie Kerr

Louie Kostidis

Poo Fun Lai

Jamie Laird

Kin Kiong Lee

Academic Staff

David Jamieson

Steven Prawer

Lloyd Hollenberg

Postdoctoral Fellows

Jeff McCallum

Paul Spizzirri

Igor Adrienko

+2

Infrastructure

Alberto Cimmino

Roland Szymanski

William Belcher

Eliecer Para

Key Personnel
  • Geoff Leech* DeborahLouGreig
  • Ming Sheng Liu
  • Glenn Moloney
  • Julius Orwa
  • Arthur Sakalleiou
  • Russell Walker
  • Cameron Wellard*
the quantum computer melbourne node
The Quantum Computer: Melbourne Node

Node Team Leader: Steven Prawer

Test structures created by single ion implantation

Atom Lithography and AFM measurement of test structures

Theory of Coherence and Decoherence

fabrication pathways
Fabrication Pathways

Fabrication strategies:

  • (1) Nano-scale lithography:
    • Atom-scale lithography using STM H-resist
    • MBE growth
    • EBL patterning of A, J-Gates
    • EBL patterning of SETs
  • (2) Direct 31P ion implantation
  • Spin measurement by SETs or magnetic resonance force microscopy
  • Major collaboration with Los Alamos National Laboratory, funded through US National Security Agency
kev electrons and mev ions interact with matter

30 keV e

60 keV e

2 MeV He

5 m

10 m

0.5 m

  • Deep probe
  • Large damage at end of range
keV electrons and MeV ions interact with matter
  • Restricted to 10 m depth, large straggling
  • Low beam damage
the melbourne pelletron accelerator
The Melbourne Pelletron Accelerator
  • Installed in 1975 for nuclear physics experiments.
  • National Electrostatics Corp. 5U Pelletron.
  • Now full time for nuclear microprobe operation.
  • Will be state-of-the-art following RIEFP upgrade

Inside

Outside

nuclear microprobe essential components

x-ray detector

1 m

From accelerator

Scanner

Beam steerer & Object collimators

Aperture collimators

Microscope

Probe forming lens

SSBs

Sample stage goniometer

Low vibration mounting

Ion pumps

Nuclear microprobe essential components
chamber inside

Re-entrant microscope

port & light

SSB detectors

SiLi port

Specimen

Chamber inside
  • 30 mm2 Si(Li) x-ray detector
  • 25 and 100 msr PIPS particle detectors at 150o
  • 75 msr annular detector
mev ions interact with matter
MeV ions interact with matter

3 MeV H+

  • MeV ions penetrate deeply without scattering except at end of range.
  • Energy loss is first by electronic stopping
  • Then nuclear interactions at end of range

PMMA substrate(side view)

surface

100 m

micomachining
Micomachining

Protons

  • Example
  • Proton beam lithography
    • PolyMethyl MethAcrylate (PMMA)
    • exposure followed by development
    • 2 MeV protons
    • clearly shows lateral straggling

10 m

Sideview

mev ion beam micromachining high aspect ratio structures in pmma

The work of Frank Watt

MeV ion beam micromachining:High aspect ratio structures in PMMA

Work done at the Nuclear Microscopy Unit at the National University of Singapore

  • 2.3 MeV protons on PMMA
  • This work dates from 1996, much more interesting structures are now available
  • See review by Prof F. Watt, ICNMTA6 - Cape Town, October 1998
mev ion beam micromachining optical materials

The work of Mark von Bibra

2 MeV H+

silica surface

laser light emerging

20m

MeV ion beam micromachining:Optical Materials
  • Fused Silica
    • Increase in density at end of range
    • Increase in refractive index (up to 2%) at end of range
single ion implantation fabrication strategy
Single Ion Implantation Fabrication Strategy

Etch latent damage& metallise

Read-out state of “qubits”

MeV 31P implant

Resist layer

Si substrate

mev ion etch pits in track detector

Light ion etch pits

Heavy ion etch pit

Scale bars: 1 mm intervals

MeV ion etch pits in track detector
  • Single MeV heavy ions are used to produce latent damage in plastic
  • Etching in NaOH develops this damage to produce pits
  • Light ions produce smaller pits

3. Etch

2. Latent damage

1. Irradiate

From: B.E. Fischer, Nucl. Instr. Meth. B54 (1991) 401.

single ion tracks
Single ion tracks
  • Latent damage from single-ion irradiation of a crystal (Bi2Sr2CaCuOx)
  • Beam: 230 MeV Au
  • Lighter ions produce narrower tracks!

Depth

1 mm

3 mm

5 mm

7.5 mm

3 nm

From Huang and Sasaki, “Influence of ion velocity on damage efficiency in the single ion target irradiation system” Au-Bi2Sr2CaCu2Ox Phys Rev B 59, p3862

high energy single ion tracks in silicon direct imaging with scanning probe microscopy
High energy single-ion tracks in silicon: direct imaging with scanning probe microscopy
  • Nanofabrication by the implantation of MeV single-ions offers a novel method for the construction of small devices which we call atomic-lithography. A leading contender for the first nano-device constructed by this method is an array of spins for a quantum computer. For the first time, we propose the use of high resolution scanning probe microscopy (SPM) to directly image irradiation-induced machining along the ion track and lattice location of the implanted ion in silicon on an atomic scale. This will allow us to measure the spatial distribution of defects and donors along the tracks to analyse the atom-scale electronic properties of the irradiated materials.

STM/AFM tip

spin array test structure
Spin array test structure
  • Aim: Create a spin array for test imaging with MRAFM

Grid

<Si>

Implant 31P through mask of 1 micron period grid

300 nm deep (220 keV 31P+)

Resulting array of 1 micron islands of spins

Number of spins in each island is 1x10-8D, D is 31P dose in P/cm2