Transcript Slides for our discussion of recent topics from the literature

Importance
This is the first demonstration of light emission
from a single carbon nanotube p-n diode and it
exhibits a narrower electroluminescent emission
spectrum and lower power consumption than
any other CNT light emitter.
Silicon nanowire-based tunneling field-effect transistors
(TFETs) on flexible plastic substrates
TFETs on polyethersulfone plastic substrate can be used for applications in low power
dissipation by scaling down the threshold voltage, which is not applicable in metal-oxidesemiconductor field-effect transistors(MOSFETs).
Lee et al.,Nanotechnology 20 (2009) 455201
Ultraflat Graphene
By: Chun Hung Lui, Li Liu, Kin Fai Mak, George W. Flynn & Tony F. Heinz
• Lui et al reported the fabrication and
characterization of high-quality ultraflat
graphene using a mica support
• Used mica because it’s easy to
create atomically flat surfaces as large
as 100µm
• Compared graphene layers on mica and
SiO2 using amplitude-modulation AFM
•Graphene layers on SiO2 roughly
follow the contours of the substrate
•Height difference in layers on mica
could be attributed to instrumental
noise
• Important because it provides insight into
thermodynamic instability of this 2-D
system
• Also provides a reference material to
study the role of ripples in graphene
a: graphene on SiO2
c: cleaved kish graphite
the data
b: graphene on mica
d: height histograms of
Ferroelectrics+Inhomogeneities=relexors
Importance: offer an insight to the physical basis of relaxors-ferroelectrics
Fu et al. Relaxor Pb(Mg1/3Nb2/3)O3: A Ferroelectric with Multiple Inhomogeneities. Phys. Rev. Lett.
(2009) vol. 103 (20) pp. 207601
An optical cloak made of dielectrics
Experiment
Simulation
Flat surface
Bump w/o a cloak
Bump w/ a cloak
To make things Invisible is interesting, and this is the
first experimental demonstration of optical cloaking.
Nature Physics, published online 2009
•
20 keV x-rays focused to 10 nm
with mirrors at Spring-8
– one laterally graded focusing
mirror
– One has 18 piezoelectric strips
glued on the back so it’s
dynamically deformable
•
•
•
Before wavefront correction
After wavefront correction
Measure profile of deformable
mirror with interferometer, use
piezos to adjust for thermal
expansion, etc.
Measure beam intensity profile
and reconstruct wavefront
Obtained stable, sub- 10nm
focus for more than 12 hours
A high-mobility electron gas at
the LaAlO3/SrTiO3 heterointerface
• Films of LaAlO3 grown on
STO substrates
• LaO/TiO2 interface showed
n-type conductivity with
high mobility
A. Ohtomo and H. Y. Hwang. Letters to Nature, 427 (2004) pp. 423-427