Openning/closing sentences in Lieber’s papers (Nature/Science/PNAS)
Branched nanostructures represent unique, 3D building blocks for the “bottom-up”
paradigm of nanoscale science and technology.
Our work demonstrates a previously undescribed level of structural and functional
complexity in NW materials, and more generally, highlights the potential of bottom-up
synthesis to yield increasingly complex functional systems in the future.
Design and rational synthesis of semiconductor nanowire (NW) building blocks with
well-defined structure and physical properties are central to the “bottom-up” approach for
nanoscience and nanotechnology (1–6).
Microbial fuel cells (MFCs) represent a promising approach for sustainable energy
production as they generate electricity directly from metabolism of organic substrates
without the need for catalysts. However, the mechanisms of electron transfer between
microbes and electrodes, which could ultimately limit power extraction, remain
controversial. Here we demonstrate optically transparent nanoelectrodes as a platform to
investigate extracellular electron transfer in Shewanella oneidensis MR-1, where an array
of nanoholes precludes or single window allows for direct microbeelectrode contacts.
The ability to control and image cell/electrode interactions down to the single-cell level
provide a powerful approach for advancing our fundamental understanding of MFCs.
The capability of bacteria, such as Shewanella and Geobacter, to transfer electrons from
metabolism of organic sources to electrodes without intervening catalysts serves as the
basis for electricity production in microbial fuel cells (MFCs) (1–7).
Nanoelectronic devices offer substantial potential for interrogating biological systems,
although nearly all work has focused on planar device designs. We have overcome this
limitation through synthetic integration of a nanoscale field-effect transistor (nanoFET)
device at the tip of an acute-angle kinked silicon nanowire, where…
Nanowire and nanotube electrical devices have been exploited for ultrasensitive detection
of biological markers (1) and high-resolution extracellular recording from cells (2–5).
However, ….have not been demonstrated because almost all examples of these devices
are created on planar substrates.
Investigations of ultrasmall light sources have opened up the possibilities of
demonstrating low-threshold lasers,1 efficient single photon sources,2 and ultrafast
modulation sources3aswellasstudyingstronglight-matterinteractions.4,5
Our demonstration and understanding of these subwavelength plasmonic lasers represent
a significant step toward faster, smaller coherent light sources.
1
Revealing the functional connectivity in natural neuronal networks is central to
understanding circuits in the brain. Here, we show that silicon nanowire field-effect
transistor (Si NWFET) arrays fabricated on transparent substrates can be reliably
interfaced to acute brain slices.
Our demonstration of simultaneous high temporal and spatial resolution recording, as
well as mapping of functional connectivity, suggest that NWFETs can become a
powerful platform for studying neural circuits in the brain.
Three-dimensional (3D), multi-transistor-layer, integrated circuits represent an important
technological pursuit promising advantages in integration density, operation speed, and
power consumption compared with 2D circuits.
These results highlight the flexibility of bottom-up assembly of distinct nanoscale
materials and suggest substantial promise for 3D integrated circuits.
The ability to control and modulate the …. during the synthesis process has allowed
researchers to explore various applications of nanowires11–15. However, despite
advances in nanowire synthesis, progress towards the ab initio design and growth of
hierarchical nanostructures has been limited. Here, we demonstrate a ‘nanotectonic’
approach that provides iterative control over the nucleation and growth of nanowires,
The incorporation of electrically active dopants in semiconductor materials has been
central to development of electronic and optoelectronic devices (1, 2).
Semiconductor nanowires (NWs) have unique electronic properties and sizes comparable
with biological structures involved in cellular communication, thus making them
promising nanostructures for establishing active interfaces with biological systems.
Recording electrical signals from cells and tissue is central to areas ranging from the
fundamental biophysical studies of function in, for example, the heart and brain, through
medical monitoring and intervention (1–3).
Our modular approach simplifies the process of interfacing cardiomyocytes and other
cells to high-performance Si-NWFETs, thus increasing the experimental versatility of
NWFET arrays and enabling device registration at the subcellular level.
The efficient delivery of photons from light sources to photonic circuits is central to any
fibre-optic or integrated optical system…. however, the efficient coupling of integrated
light sources into nanophotonic circuits remains a challenge. Here, we propose an
optically or electrically driven photonic structure that uses active semiconductor
nanowires to light up photonic-crystal waveguides.
The hybrid nanowire/photonic-crystal waveguide represents a significant advance
towards all-optical processing in nanoscale integrated photonic circuits and a new
addition to the nanophotonic toolbox.
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Rational design and synthesis of nanowires with increasingly complex structures can
yield enhanced and/or novel electronic and photonic functions1,2.
Our work demonstrates a new level of complexity in nanowire structures, which
potentially can yield free-standing injection nanolasers.
Miniaturized multicolour lasers could be enabled with the development of a tunablebandgap nanoscale gain medium that is coupled effectively into a small optical cavity.
Free-standing nanowires have received considerable attention as nanolasers7–13,
where the semiconductor nanowires have functioned as both the gain medium and optical
cavity. So far…
Electronics obtained through the bottom-up approach of molecular-level control of
material composition and structure may lead to devices and fabrication strategies not
possible with top-down methods.
Solar cells are attractive candidates for clean and renewable power1,2; with
miniaturization, they might also serve as integrated power sources for nanoelectronic
systems…. However, solar cells based on hybrid nanoarchitectures suffer from relatively
low efficiencies and poor stabilities1. In addition, previous studies have not yet addressed
their use as photovoltaic power elements in nanoelectronics. Here we report the
realization of ….
These coaxial silicon nanowire photovoltaic elements provide a new nanoscale test bed
for studies of photoinduced energy/charge transport and artificial photosynthesis10,
and might find general usage as elements for powering ultralowpower electronics11 and
diverse nanosystems12,13.
One proposal for a solid-state-based quantum bit (qubit) is to control coupled electron
spins on adjacent semiconductor quantum dots1,2. Most experiments have focused on
quantum dots made from III–V semiconductors; however, the coherence
of electron spins in these materials is limited by…
Many of the applications proposed for nanowires and carbon nanotubes require these
components to be organized over large areas with controlled orientation and density.
Although progress has been made with directed assembly and Langmuir–Blodgett
approaches, it is unclear whether these techniques can be scaled to large wafers and nonrigid substrates. Here, we describe a general and scalable approach for large-area,
uniformly aligned and controlled-density nanowire and nanotube films,
Our approach could allow the unique properties of nanowires and nanotubes to be
exploited in applications requiring large areas and relatively modest device densities.
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Semiconductor nanowires (NWs) and carbon nanotubes (NTs) exhibit physical properties
that make them attractive building blocks for many electronic and optical applications1–3.
The controlled growth of nanowires (NWs) with dimensions comparable to the Fermi
wavelengths of the charge carriers allows fundamental investigations of quantum
confinement phenomena.
The ability to create and control coherent superconducting ordered states in
semiconductor–superconductor hybrid nanostructures allows for new opportunities in the
study of fundamental low-dimensional superconductivity.
Detection and quantification of biological and chemical species are central to many areas
of healthcare and the life sciences, ranging from diagnosing disease to discovery and
screening of new drug molecules.
Electrophysiological measurements made with micropipette electrodes and
microfabricated electrode arrays play an important role in understanding signal
propagation through individual neurons and neuronal networks (1–5).
Semiconducting carbon nanotubes1,2 and nanowires3 are potential alternatives to planar
metal-oxide-semiconductor field-effect transistors (MOSFETs)4 owing, for example, to
their unique electronic structure and reduced carrier scattering caused by one-dimensional
quantum confinement effects1,5…. Yet whether nanowire fieldeffect transistors
(NWFETs) can indeed outperform their planar counterparts is still unclear4.Here we
report studies on…
Integrating nanophotonics with electronics could enhance and/or enable opportunities in
areas ranging from communications and computing to novel diagnostics1,2.
NanoAPDs and arrays could open new opportunities for ultradense integrated systems,
sensing and imaging applications.
Electronic devices fabricated with designed modulation-doped nanowire structures
demonstrate their potential for lithography-independent address decoders and tunable,..
Carbon nanotubes and semiconductor nanowires have attracted considerable attention as
1D structures for fundamental studies and also as potential building blocks for
nanodevices (1–3).
The possibility of large-scale integration of these nanowire devices suggests potential for
simultaneous detection of a large number of distinct viral threats at the single virus level.
Substantial effort has been placed on developing semiconducting carbon nanotubes1–3
and nanowires4 as building blocks for electronic devices—such as field-effect
transistors—that could replace conventional silicon transistors in hybrid electronics or
lead to stand-alone nanosystems4,5….
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The development of strategies for addressing arrays of nanoscale devices is central to the
implementation of integrated nanosystems such as biological sensor arrays and
nanocomputers. We report a general approach for addressing
These results provide a step toward the realization of addressable integrated nanosystems
in which signals are restored at the nanoscale.
The past several decades have witnessed major advances in computing that have resulted
from systematic reductions in feature sizes and the corresponding increases in integration
densities achieved by the semiconductor industry (1).
Electrically driven semiconductor lasers are used in technologies ranging from
telecommunications and information storage to medical diagnostics and therapeutics1.
The success of this class of lasers is due in part to well-developed planar semiconductor
growth and processing, which enables reproducible fabrication of integrated, electrically
driven devices2,3. Yet this approach to device fabrication is also costly and difficult to
integrate directly with other technologies such as silicon microelectronics. To overcome
these issues for future applications, there has been considerable interest in using organic
molecules4,5, polymers6,7… Electrically driven semiconductor lasers are used in
technologies ranging from telecommunications and information storage to medical
diagnostics and therapeutics1.
Electrically driven nanowire lasers, which might be assembled in arrays capable of
emitting a wide range of colours, could improve existing applications and suggest new
opportunities.
However, modulation of the radial composition and doping in nanowire structures has
received much less attention than planar1 and nanocrystal7 systems.
Our synthesis of core–multishell structures, including a high-performance coaxially gated
field-effect transistor, indicates the general potential of radial heterostructure growth for
the development of nanowire-based devices.
The assembly of semiconductor nanowires and carbon nanotubes into nanoscale devices
and circuits could enable diverse applications in nanoelectronics and photonics
Single-nanowire photoluminescence, electrical transport and electroluminescence
measurements show the unique photonic and electronic properties of these nanowire
superlattices, and suggest potential applications ranging from nano-barcodes to polarized
nanoscale LEDs.
Our approach to superlattice growth (Fig. 1) exploits recent developments in metalcatalysed nanowire synthesis, which have shown that
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Miniaturization in electronics through improvements in established top-down fabrication
techniques is approaching the point where fundamental issues are expected to limit the
dramatic increases in computing seen over the past several decades.
The facile assembly of key electronic device elements from welled Þned nanoscale
building blocks may represent a step toward a bottom-up paradigm for electronics
manufacturing.
Miniaturization of silicon electronics is being intensely pursued (1), although
fundamental limits of lithography may prevent current techniques from reaching the deep
nanometer regime for highly integrated devices (2).
Our studies demonstrate a rational approach for building key nanoscale electronic
devices from SiNWs that have controlled carrier type and concentration, and thus
represent a step toward a “bottom-up” paradigm for electronics manufacturing.
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