28-11-2012, 01:32 PM
Nanoscale Materials and Devices for Future Communication Networks
[attachment=41469]
ABSTRACT
New discoveries in materials on the nanometer-
length scale are expected to play an important
role in addressing ongoing and future
challenges in the field of communication.
Devices and systems for ultra-high-speed shortand
long-range communication links, portable
and power-efficient computing devices, highdensity
memory and logics, ultra-fast interconnects,
and autonomous and robust energy
scavenging devices for accessing ambient intelligence
and needed information will critically
depend on the success of next-generation emerging
nanomaterials and devices. This article presents
some exciting recent developments in
nanomaterials that have the potential to play a
critical role in the development and transformation
of future intelligent communication networks.
INTRODUCTION
During the last two decades, significant progress
has been made in controlling and engineering
new materials on the nanometer-length scale —
at the level of atoms, molecules, and supramolecular
structures. Many of these nanostructured
materials have shown tremendous promise as
building blocks for scalable, miniature, and energy-
efficient electronics, photonics, magnetics,
and electromechanical systems to transform
computing and communication in the future.
Key progress in all these areas will convincingly
transform future communications links to facilitate
faster data transfer rates for connections
with ubiquitous intelligent ambient systems at
home, in the office, and in public places. At present,
these nanodevices for miniaturized processors,
memory, circuits, interconnects, and
possibly future self-powered computing systems
with unprecedented intelligence, energy efficiency,
and scalability are progressively posing an
engineering and technological challenge rather
than remaining as a field of fundamental
research. A highly multidisciplinary endeavor
and significant successes in the commercialization
of nanomaterials and nanodevices will no
doubt lead to strong potential for high economic
impact comparable to the telecommunication
technology of the 1990s and the information
technology growth of the last decade.
NANOHETEROEPITAXY FOR
OPTICAL INTERCONNECTS
Direct integration of an assortment of semiconductor
nanostructures in devices and circuits on
single crystal surfaces offers attractive opportunities
in several areas of high-performance communication
electronics, optoelectronics, sensing,
energy conversion, and imaging. Beyond these
applications, integration of a range of nanostructures
on amorphous surfaces offers unlimited
capabilities for multifunctional materials and
device integration. In fact, the possibility of lowcost
electronics and photonics based on such an
approach would dwarf silicon photonics and
other competing technologies. The key constraints
in growing planar epitaxial thin film of a
semiconductor on another single crystal substrate
are lattice and thermal expansion coefficient
mismatches, material incompatibilities, and
differences in crystal structure [3].
OUT-OF-PLANE OPTICAL INTERCONNECTS
Optical pillars and wires along with microphotonics
technology were employed to demonstrate
external optical interconnects that can connect
different parts of electronic chips via air or fiber
cables at the expense of a bulky configuration
[8]. Unfortunately, optical devices (laser, modulators,
and detectors) and light guides are
~1000× larger in physical dimensions than electronic
components, and it is very challenging to
combine these two technologies on the same cir-
cuit. State-of-the-art electronic devices are fabricated
with feature sizes in the range of tens of
nanometers, and emerging electronic devices
such as single electron transistors are designed
with sub-nanometer dimensions. On the other
hand, optical devices can reach a theoretical size
limit on the order of the wavelengths (~1 μm) if
sophisticated techniques such as photonic crystals
are used.
PHOTONIC CRYSTALS
The concept of photonic bandgap crystals has
been around for more than two decades. A line
defect within a two-dimensional photonic
bandgap crystal provides efficient spatial confinement
of light, and works as a building block
in a variety of routing and processing schemes of
light. In contrast, silicon in the form of the
CMOS technology platform has been the core
driver in microelectronics. Silicon nanophotonics,
which allows CMOS platforms to handle
light, thus would offer a wide range of photonic
functions required for CMOS platforms to push
further progress in high-speed data transfer
rates. Nanophotonic implementations of wavelength
multiplexers and demultiplexers by
employing photonic crystals or non-periodic
nanophotonic structures offer greatly reduced
footprints and enhanced robustness to fabrication
tolerances and temperature variations.
While the photonic bandgap crystal and silicon
nanophotonics are still subject to the diffraction
limit of light, photonic devices that use surface
plasmon polaritons (SPPs) and/or energy transfer
mechanisms relying on optical near-field
interactions would pave the road toward ultimate
photonic integration beyond the diffraction
limit of light.
[attachment=41469]
ABSTRACT
New discoveries in materials on the nanometer-
length scale are expected to play an important
role in addressing ongoing and future
challenges in the field of communication.
Devices and systems for ultra-high-speed shortand
long-range communication links, portable
and power-efficient computing devices, highdensity
memory and logics, ultra-fast interconnects,
and autonomous and robust energy
scavenging devices for accessing ambient intelligence
and needed information will critically
depend on the success of next-generation emerging
nanomaterials and devices. This article presents
some exciting recent developments in
nanomaterials that have the potential to play a
critical role in the development and transformation
of future intelligent communication networks.
INTRODUCTION
During the last two decades, significant progress
has been made in controlling and engineering
new materials on the nanometer-length scale —
at the level of atoms, molecules, and supramolecular
structures. Many of these nanostructured
materials have shown tremendous promise as
building blocks for scalable, miniature, and energy-
efficient electronics, photonics, magnetics,
and electromechanical systems to transform
computing and communication in the future.
Key progress in all these areas will convincingly
transform future communications links to facilitate
faster data transfer rates for connections
with ubiquitous intelligent ambient systems at
home, in the office, and in public places. At present,
these nanodevices for miniaturized processors,
memory, circuits, interconnects, and
possibly future self-powered computing systems
with unprecedented intelligence, energy efficiency,
and scalability are progressively posing an
engineering and technological challenge rather
than remaining as a field of fundamental
research. A highly multidisciplinary endeavor
and significant successes in the commercialization
of nanomaterials and nanodevices will no
doubt lead to strong potential for high economic
impact comparable to the telecommunication
technology of the 1990s and the information
technology growth of the last decade.
NANOHETEROEPITAXY FOR
OPTICAL INTERCONNECTS
Direct integration of an assortment of semiconductor
nanostructures in devices and circuits on
single crystal surfaces offers attractive opportunities
in several areas of high-performance communication
electronics, optoelectronics, sensing,
energy conversion, and imaging. Beyond these
applications, integration of a range of nanostructures
on amorphous surfaces offers unlimited
capabilities for multifunctional materials and
device integration. In fact, the possibility of lowcost
electronics and photonics based on such an
approach would dwarf silicon photonics and
other competing technologies. The key constraints
in growing planar epitaxial thin film of a
semiconductor on another single crystal substrate
are lattice and thermal expansion coefficient
mismatches, material incompatibilities, and
differences in crystal structure [3].
OUT-OF-PLANE OPTICAL INTERCONNECTS
Optical pillars and wires along with microphotonics
technology were employed to demonstrate
external optical interconnects that can connect
different parts of electronic chips via air or fiber
cables at the expense of a bulky configuration
[8]. Unfortunately, optical devices (laser, modulators,
and detectors) and light guides are
~1000× larger in physical dimensions than electronic
components, and it is very challenging to
combine these two technologies on the same cir-
cuit. State-of-the-art electronic devices are fabricated
with feature sizes in the range of tens of
nanometers, and emerging electronic devices
such as single electron transistors are designed
with sub-nanometer dimensions. On the other
hand, optical devices can reach a theoretical size
limit on the order of the wavelengths (~1 μm) if
sophisticated techniques such as photonic crystals
are used.
PHOTONIC CRYSTALS
The concept of photonic bandgap crystals has
been around for more than two decades. A line
defect within a two-dimensional photonic
bandgap crystal provides efficient spatial confinement
of light, and works as a building block
in a variety of routing and processing schemes of
light. In contrast, silicon in the form of the
CMOS technology platform has been the core
driver in microelectronics. Silicon nanophotonics,
which allows CMOS platforms to handle
light, thus would offer a wide range of photonic
functions required for CMOS platforms to push
further progress in high-speed data transfer
rates. Nanophotonic implementations of wavelength
multiplexers and demultiplexers by
employing photonic crystals or non-periodic
nanophotonic structures offer greatly reduced
footprints and enhanced robustness to fabrication
tolerances and temperature variations.
While the photonic bandgap crystal and silicon
nanophotonics are still subject to the diffraction
limit of light, photonic devices that use surface
plasmon polaritons (SPPs) and/or energy transfer
mechanisms relying on optical near-field
interactions would pave the road toward ultimate
photonic integration beyond the diffraction
limit of light.