nano magnetic interactions on mnas thin films
DESCRIPTION
Research proposal on the interactions of ferromagnetic nanoparticles with MnAs thin films. Published in APL.TRANSCRIPT
Nano-magnetic interactions Nano-magnetic interactions on MnAs thin filmson MnAs thin films
Raphael BouskilaRaphael BouskilaM.Sc. CandidateM.Sc. Candidate
Burch Group, University of TorontoBurch Group, University of Toronto
09/24/13 R. Bouskila / K. Burch 2
OutlineOutline MotivationMotivation ObjectivesObjectives Description of proposed experimentDescription of proposed experiment Further research ideasFurther research ideas
09/24/13 R. Bouskila / K. Burch 3
MotivationMotivation What are we trying to do here?What are we trying to do here? We are studying the interactions of We are studying the interactions of
ferromagnetic domains on the nanoscaleferromagnetic domains on the nanoscale
09/24/13 R. Bouskila / K. Burch 4
MotivationMotivation Example application: BiosensorsExample application: Biosensors
– Chemical purity measurementsChemical purity measurements– Drug uptake measurementsDrug uptake measurements– Organic molecule selection via functionalized Organic molecule selection via functionalized
nanoparticlesnanoparticles
09/24/13 R. Bouskila / K. Burch 5
MotivationMotivation Example: DNA strings ligated to magnetic Example: DNA strings ligated to magnetic
nanoparticles (e.g., Horák, nanoparticles (e.g., Horák, J. Mag. & Mag. J. Mag. & Mag. Mater.Mater. 311 311 249 (2007))249 (2007))– Specific DNA/RNA strings attach to the Specific DNA/RNA strings attach to the
particles, and then the DNA can be selected particles, and then the DNA can be selected out via the properties of the particle attached out via the properties of the particle attached to itto it
09/24/13 R. Bouskila / K. Burch 6
IntroductionIntroduction MnAs: two-phase MnAs: two-phase
system near RTsystem near RT– Domain width: ~100 Domain width: ~100
nmnm– Period: ~200 nmPeriod: ~200 nm
Can be controlled via:Can be controlled via:– Optical excitationOptical excitation– Ambient temperatureAmbient temperature
09/24/13 R. Bouskila / K. Burch 7
IntroductionIntroduction
α-MnAs(ferromagnetic)
β-MnAs(paramagnetic)
09/24/13 R. Bouskila / K. Burch 8
IntroductionIntroduction MnAs in profile:MnAs in profile:
GaAs (001) substrate
H
α-MnAs
β-MnAs
60 nm
100 nm
09/24/13 R. Bouskila / K. Burch 9
IntroductionIntroduction Alternatively:Alternatively:
GaAs (001) substrate
H
α-MnAs
β-MnAs
60 nm
100 nm
09/24/13 R. Bouskila / K. Burch 10
IntroductionIntroduction Goh group (Dept. of Chemistry, University Goh group (Dept. of Chemistry, University
of Toronto), produces ferromagnetic of Toronto), produces ferromagnetic nanoparticlesnanoparticles– ~10-20 nm diameter~10-20 nm diameter– Composed of iron oxideComposed of iron oxide– Water-solubleWater-soluble
09/24/13 R. Bouskila / K. Burch 11
ObjectivesObjectives Proof-of-concept idea:Proof-of-concept idea:
GaAs (001) substrate
H
60 nm
100 nm
09/24/13 R. Bouskila / K. Burch 12
MethodMethod
09/24/13 R. Bouskila / K. Burch 13
ResultsResults
09/24/13 R. Bouskila / K. Burch 14
ResultsResults
09/24/13 R. Bouskila / K. Burch 15
ResultsResults
09/24/13 R. Bouskila / K. Burch 16
ResultsResults
09/24/13 R. Bouskila / K. Burch 17
Further ideasFurther ideas Do different nanowire widths preferentially Do different nanowire widths preferentially
trap different sizes of nanoparticle?trap different sizes of nanoparticle? Could a temperature or optical energy Could a temperature or optical energy
gradient sort particles by size?gradient sort particles by size? Can this method be used as a “poor man’s Can this method be used as a “poor man’s
MFM” technique?MFM” technique? Can this method be used to align Can this method be used to align
nanoparticles into arbitrary patterns?nanoparticles into arbitrary patterns?
Thanks!Thanks!