The world of nanomaterials and the study of nanoscale interactions span a
hugely important and wide-ranging sector of modern science and industry. It
is easy to forget how rapidly their prominence has grown since the turn of
this century, when nanoscience and nanotechnology were still essentially in
their infancy. At that time, the propagation of some fantastically inflated
speculation—and considerable scaremongering in some quarters—had
become sufficiently rife that anything with a ‘nano’ prefix was in danger of
being regarded either as pure hype, or as something associated with
irresponsibly high risk. Yet those most closely involved saw the true potential,
recognizing the need for safeguards and for investment to support advances
that could hold genuinely transformative potential.
As key decision makers in increasing numbers became persuaded of the
solidity and promise of the subject, the next few years saw a spate of Institute
of Nanoscience foundations, such as those in Pittsburgh in 2002, NRL (U.S.
Naval Research Laboratory) in 2003, Delft in 2004, and both Iowa City and
Basel in 2006. At around the same time, the increasing number of
presentations on ‘nano’ topics began to draw the attention of conference
organizers and managers, leading to new streams of conference material. With
customary vision, SPIE led the forefront of developments with an aim to
provide a central forum for such topics and to stimulate and support their
growth. Starting with a workshop on nanomaterials in 2002, the structuring of
conferences at its annual summer meeting (most often in San Diego) was
purposefully focused and extended into a cohesive stream of content that
emerged into its now familiar form, the Nanoscience and Engineering
Symposium.
It is a pleasure and honor to have been involved in this symposium since
the outset, alongside my friend and colleague Jim Grote. It has been our great
delight to witness the growth in size and reputation of the symposium and to
find so many internationally eminent individuals—more than sixty since the
inception in 2002—prepared to come and deliver plenary lectures. The present
monograph represents a careful selection of chapters from some of those most
closely involved; their contributions aim to bring the reader up to date with
the numerous advances that continue to shape and reshape the subject. In this International Year of Light, it is particularly appropriate that a large number
of these advances relate to optical materials, interactions, or measurements.
Indeed, the prominence of light-related topics in the whole sphere of
nanoscience research and development befits the positioning of the
Nanoscience and Engineering Symposium within SPIE’s Optics and Photonics
event. Yet, the subject matter extends well beyond the boundaries of
nanophotonics and nano-optics, and its true interdisciplinarity will be more
than evident in the pages that follow.
In Chapter 1, He et al. describe how advanced methods of nanofabrication
now enable the construction of nanowaveguides whose performance can be
enhanced by harnessing plasmonic interactions, or, for example, by the
incorporation of graphene elements. Such devices provide a basis for a variety
of emerging applications in polarizers, optical communications, high-sensitivity,
real-time biosensing, and light harvesting. Pavesi et al., in Chapter 2, also
discuss engineered nanostructures, here with a focus on silicon photonics. This
is a growth area in its own right, since silicon offers scope to reduce the massive
power demands of major communications routers such as those engaged in
Internet search engines. Although the prospect of a relative ease of integration
with existing semiconductor fabrication methods is attractive, true integration is
limited by the complexity of integrated photonic circuits. This chapter shows
how some of the outstanding problems can be circumvented or mitigated.
Silicon microresonators have significant applications in biosensing and in
optomechanics.
Chapter 3 by Lee et al. concerns an important area of application for
nonlinear optics, in which two-photon-induced polymerization or allied
lithography methods are deployed in the 3D microfabrication of polymeric,
organic, and inorganic materials. The full capability of such an approach can
be gauged by its capacity to create complex regular structures such as
photonic crystals, using a photoresist incorporating a dye with a large twophoton-
absorption cross section. The same technique can be adapted for the
nanofabrication of atomic force microscopy tips, or components in
microfluidic motors. Campo et al., in Chapter 4, then describe the use of
structure-determining methods such as near-edge x-ray absorption fine
structure (NEXAFS) or Raman spectroscopy to achieve a better understanding
of the noncovalent interactions that determine the bulk physical properties
of many novel polymeric composites. Here, particular interest is in composites
incorporating carbon nanotubes, which can lead to dramatic improvements in
mechanical, thermal, electrical, and optical properties. Such composites hold
promise for commercial applications that include textiles, fuselage constructs,
and haptic screens.
In Chapter 5, Monti and Armaroli discuss the principles of molecular
engineering for solar energy conversion and new materials for lighting—areas
linked by a common dependence on electron- and energy-transfer pathways, typically involving molecular complexes and fullerenes as well as transitionmetal
ions. With the global drive toward lower energy consumption and a
reduced dependence on fossil fuels, these materials are helping to address the
continuing need to develop higher efficiency and better quality lighting.
Chapter 6, by Sullivan and Dalton, then takes a comprehensive look at
theory-guided principles for the design of organic electro-optical materials
and silicon/plasmonic–organic hybrids. Recent advances in this area provide
the means to engineer for improved control of material viscoelasticity,
reductions in optical loss, and increases in both thermal and photochemical
stability.
The subject of the subsequent three chapters is biomaterials and
biopolymers. This is another area of significant recent development, in which
the often astonishingly propitious physical properties of natural biological
materials are exploited in new products. Chapter 7 by Grote et al. deals with
photonic applications, and Chapter 8, also by Grote et al., covers electronic
applications, showing that many of the most promising new materials are
formed as films or composites from DNA biopolymers. Such polymers have
optical properties that are often comparable in performance or, in many cases,
superior to traditional polymers. Moreover, they prove to be especially robust
against UV or gamma radiation and are therefore materials potentially
suitable for future space-based applications. Yet another class of biomaterials
discussed by Melucci and Zamboni in the concluding Chapter 9 are those
based on silk fibroin, sustainably fabricated by reverse engineering from
silkworm cocoons. Here, composites with functional organic compounds
provide the basis for a wide range of tailored materials with exciting new
properties, suited for the manufacture of multifunctional bioactive devices.
I commend this volume to its readers as an indication of the breadth and
scale of recent advances in nanoscience. And in conclusion, I offer sincere
thanks to all contributors for delivering manuscripts of such high quality,
comprehensively covering such a wide a range of topics, and to the invariably
helpful and professional staff of SPIE’s publishing division, who have strongly
supported this project from the start and have brought it to a timely fruition.
David L. Andrews
Norwich, U.K.
July 2015
