Plasmonics promises Faster Communication

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The term ‘plasmonics’ is derived from
plasmons—quanta associated with surface charge oscillations. Their
frequency is almost equal to that of light;
optical frequencies are about 105 times
greater than the frequency of today’s
electronic microprocessors. So light can
be used to excite them on the surface of
a material in a localised regime.
The energy required to receive and
send a surface plasmon pulse can be
less than for electric charging of a metallic
wire. This could allow plasmons
to travel along nanoscale wires (called
interconnects) carrying information
from one part of a microprocessor to
another with a high bitrate.
Plasmonic interconnects would be
a great boon for chip designers, who
have been able to develop ever smaller
and faster transistors but have had a
harder time building minute electronic
circuits that can move data quickly
across the chip.


Limitations of present modes

Presently, electronics plays an important
role in communication. In laboratories,
though, photonics has started
replacing electronics where a high data
transfer rate is required.
Electronics deals with the flow of
charge (electrons). When the frequency
of an electronic pulse increases, the
electronic device becomes hot and
wires become very loose


Communication with plasmonics

Plasmonic structures can exert huge
control over electromagnetic waves at the nanoscale. As a result, energy
carried by plasmons allows for light
localisation in ultra-small volumes—
far beyond the diffraction limit of light.
To generate surface plasmons, it is
necessary to excite the metal-dielectric
interface in which the dielectric constant
of the metal is a function of frequency
and negative. At the nanoscale,
the electromagnetic (EM) field of the
EM wave displays the electron cloud
due to its well coupling, which is not
possible in the case of bulk matter.


Latest developments
The possibility to confine light to
the nanoscale and the ability to tune
the dispersion relation of light have
evoked large interest and led to rapid
growth of plasmonic research. The
parallel development of nanoscale
fabrication techniques like electron
beam lithography and focused-ionbeam
milling has opened up new
ways to structure metals’ surfaces
and control surface plasmon polariton
propagation and dispersion at the
nanoscale.