Technical Programme - Materials Research Society of Singapore ...

ICMAT 2009 and IUMRS - ICA 2009 Technical Programme
attributed to compressive strain induced by the substrate.
We demonstrate that the electronic structures of EG grown
on Si- and C-terminated SiC substrates are quite different.
We demonstrate that EG thermally grown on 6H-SiC(0001)
can be p-doped via a novel surface transfer doping scheme
of modifying the surface with the electron acceptor,
tetrafl uoro-tetracyanoquinodimethane (F4-TCNQ)
[9]. PES reveals that electron transfer from graphene
to adsorbed F4-TCNQ is responsible for the p-type
doping of graphene. This surface transfer doping scheme
by surface modifi cation with appropriate molecular
acceptors represents a simple and effective method to
non-destructively dope EG for future nanoelectronics
applications. Preliminary molecular self-assembly studies
on EG will also be discussed.
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Plenary Lecture 4
Wednesday, 1 July 2009
08:30 – 09:15 hrs
Level 2, Ballroom
Chair:
LIM Hock
Temasek Lab, Singapore
Sir John B. PENDRY
FRS, The Blackett Laboratory, Imperial College, UK
Metamaterials, Non Linear Plasmonic Phenomena and
Negative Refraction at Optical Frequencies
Negative refraction is a new phenomenon in optics that
gives access to many remarkable possibilities. Perhaps
the most remarkable of these is the prescription for
focussing light with resolution limited only by precision of
manufacture, not by intrinsic physics. Demonstrations have
been made for microwaves and even at optical frequencies
but the latter are so far confi ned to very small distances of
less than a micron. Here we propose a scheme designed
to give negative refraction of light on everyday length
scales. The scheme exploits the link between negative
refraction and phase conjugation which can be represented
as a transition between positive and negative frequency
states, but requires non linearity. Metamaterials are ideally
placed to enhance and exploit non linear phenomena. The
sub wavelength structures that comprise metamaterials
will typically concentrate the energy of incident radiation
in a very small volume and this in turn leads to substantial
enhancement of non linear effects. An experimental
realisation is proposed and under ideal circumstances this
lens can exhibit sub wavelength resolution limited only by
the strength of the phase conjugated signal.