1. Seminar Report
on
NANOTECHNOLOGY
Submitted in partial fulfillment of the requirement for the degree of B.Tech-8th
Semester
In
Information And Technology
Submitted to Submitted by
Mrs. Shabnam Khan Sanchit Sharma
Lecturer(CSE/IT) B.Tech (IT) 8th-Sem.
Department of Computer Science & Engineering
Applied College of Management & Engineering
72-Km Stone, Delhi-Mathura Road, Mitrol, Palwal-Haryana
www.acmecollege.in
2. Acknowledgement
The confidence one attains while performing a task that has great importance of its own
comes not only through one’s own constant efforts but rather is a result of ceaseless
cooperation, constant guidance and ever motivating tips of various experienced people.
I express my sincere gratitude to HOD Jatin Verma for his guidance and especially for his
emphasis on systematic approach, details and rigor in the process of research. I cherish the
discussions I had with him and thank him for his advice and all the support throughout my
research work.
I am grateful to Mrs. Shabnam Khan for her guidance and especially, for her constant
encouragement for developing a deep passion towards research and emphasis on hard work
and rigorous experimentation.
I would also like to thank the faculty members of the my institute with whom I had fruitful
interactions
.
Sanchit Sharma
2
3. Abstract
For many decades, nanotechnology has been developed with cooperation from researchers in
several fields of studies including physics, chemistry, biology, material science, engineering, and
computer science. Nanotechnology is engineering at the molecular (groups of atoms) level. It is
the collective term for a range of technologies, techniques and processes that involve the
manipulation of matter at the smallest scale (from 1 to 100 nm2).The nanotechnology provides
better future for human life in various fields. In future nanotechnology provides economy, eco
friendly and efficient technology which removes all difficult predicaments which is faced by us
in today life scenario. Nanotechnology is the technology of preference to make things small,
light and cheap, nanotechnology based manufacturing is a method conceived for processing and
rearranging of atoms to fabricate custom products.
The nanotechnology applications have three different categories nanosystems, nanomaterials and
nanoelectronics. The impact of the nanotechnology occurred on computing and data storage,
materials and manufacturing, health and medicine, energy and environment, transportation,
national security and space exploration. There are many applications of nanotechnology which
are exciting in our life such as nanopowder, nanotubes, membrane filter, quantum computers etc.
But there are several problems which are occurred with the exploration of the nanotechnology
such as the wastes released while making the materials for nanotechnology are released into the
atmosphere and can even penetarte human and animal cells and effect their performance,
agricultural countries will lose their income as nanotechnology will take over, if any damage is
done at the molecular level then it is not possible to revert it.
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4. CONTENTS
1. Introduction to Nanotechnology………………………………….... 04
2. History of Nanotechnology….…………………………………….....05
3. Concept……………………………………………………………… 06
3.1 A material perspective……………………………………06
3.2 Nano Mechanics and bio materials. ……….……………07
4. Nanotechnology Tools………………………………………………08
4.1 Transmission Electron Microscope (TEM)…………………..08
4.2 Atomic Force Microscope (AFM)…………………………….08
4.3 Scanning Tunneling Microscope (STM)……………………..09
5. Future Nanotechnology Applications……………………………....10
6. Exciting Applications of Nanotechnology..................................…...14
6.1 Nanopowders………………………………………………….14
6.2 Membranes……………………………………………………15
6.3 Carbon Nanotube……………………………………………..16
6.4 Molecular electronics…………………………………………17
6.5 Quantum Computers…………………………………………17
6.6 NanoRobotics………………………………………………….18
7. Conclusion…………………………………………………………..19
8. References …………………………………………………………………...20
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5. Chapter 1
Introduction
Nanotechnology is engineering at the molecular (groups of atoms) level. It is the collective term
for a range of technologies, techniques and processes that involve the manipulation of matter at
the smallest scale from 1 to 100 nm2 (1 nm = 0.000000001 m).
The classical laws of physics and chemistry do not readily apply at this very small scale for two
reasons. Firstly, the electronic properties of very small particles can be very different from their
larger cousins. Secondly, the ratio of surface area to volume becomes much higher, and since the
surface atoms are generally most reactive, the properties of a material change in unexpected
ways. For example, when silver is turned into very small particles, it takes on anti-microbial
properties while gold particles become any colour you choose. Nature provides plenty of
examples of materials with properties at the nanoscale – such as the iridescence of butterfly
wings, the sleekness of dolphin skin or the ‘nanofur’ that allows geckos to walk up vertical
surfaces.
Nanotechnology is not confined to one industry, or market. Rather, it is an enabling set of
technologies that cross all industry sectors and scientific disciplines. Probably uniquely, it is
classified by the size of the materials being developed and used, not by the processes being used
or products being produced. Nanoscience is inherently multidisciplinary: it transcends the
conventional boundaries between physics, chemistry, biology, mathematics, information
technology, and engineering. This also means it can be hard to define – is the introduction of
foreign genes or proteins into cells biotechnology or nanotechnology? And since genes have
genetic memory, might this also be a form of information technology? The answer is probably
‘all of the above’. The important point is that the integration of these technologies and their
manipulation at the molecular and sub-molecular level will over the next decade provide major
advances across many existing industries and create whole new industries.
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6. Chapter 2
History
Richard Feynman, US physicist and Nobel Prize winner, presented a talk to the American
Physical Society annual meeting entitled There’s Plenty of Room at the Bottom. In his talk,
Feynman presented ideas for creating nanoscale machines to manipulate, control and image
matter at the atomic scale. Prof. Feynman described such atomic scale fabrication as a bottom-
up approach, as opposed to the top-down approach that we are accustomed to. Top-down
manufacturing it involves the construction of parts through methods such as cutting, carving and
molding. Using these methods, we have been able to fabricate a remarkable variety of machinery
and electronics devices. Bottom-up manufacturing would provide components made of single
molecules, which are held together by covalent forces that are far stronger than the forces that
hold together macro-scale components. Further more, the amount of information that could be
stored in devices build from the bottom up would be enormous.
In 1974, Norio Taniguchi introduced the term ‘nanotechnology’ to represent extra-high
precision and ultra-fine dimensions, and also predicted improvements in integrated circuits,
optoelectronic devices, mechanical devices and computer memory devices. This is the so called
‘top-down approach’ of carving small things from large structures. In 1986, K. Eric Drexler in
his book Engines of Creation discussed the future of nanotechnology, particularly the creation of
larger objects from their atomic and molecular components, the so called ‘bottom-up approach’.
He proposed ideas for ‘molecular nanotechnology’ which is the self assembly of molecules into
an ordered and functional structure.
The invention of the scanning tunneling microscope by Gerd Binnig and Heinrich Rohrer in
1981 (IBM Zurich Laboratories), provided the real breakthrough and the opportunity to
manipulate and image structures at the nanoscale. Subsequently, the atomic force microscope
was invented in 1986, allowing imaging of structures at the atomic scale. Another major
breakthrough in the field of nanotechnology occurred in 1985 when Harry Kroto, Robert Curl
and Richard Smalley invented a new form of carbon called fullerenes (‘buckyballs’), a single
molecule of 60 carbon atoms arranged in the shape of a soccer ball. This led to a Nobel Prize in
Chemistry in 1996.
Since that time, nanotechnology has evolved into one of the most promising fields of science,
with multi-billion dollar investments from the public and private sectors and the potential to
create multi-trillion dollar industries in the coming decade.
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7. Chapter 3
Concept Of Nanotechnology
Atoms and molecules stick together because they have complementary shapes that lock together,
or charges that attract. Just like with magnets, a positively charged atom will stick to a negatively
charged atom. As millions of these atoms are pieced together by nanomachines, a specific
product will begin to take shape. The goal of molecular manufacturing is to manipulate atoms
individually and place them in a pattern to produce a desired structure.
The first step would be to develop nanoscopic machines, called assemblers, that scientists can
program to manipulate atoms and molecules at will. Rice University Professor Richard Smalley
points out that it would take a single nanoscopic machine millions of years to assemble a
meaningful amount of material. In order for molecular manufacturing to be practical, you would
need trillions of assemblers working together simultaneously. Eric Drexler believes that
assemblers could first replicate themselves, building other assemblers. Each generation would
build another, resulting in exponential growth until there are enough assemblers to produce
objects.
Nanotechnology is not confined to one industry, or market. Rather, it is an enabling set of
technologies that cross all industry sectors and scientific disciplines. Probably uniquely, it is
classified by the size of the materials being developed and used, not by the processes being used
or products being produced. Nanoscience is inherently multidisciplinary: it transcends the
conventional boundaries between physics, chemistry, biology, mathematics, information
technology, and engineering. This also means it can be hard to define – is the introduction of
foreign genes or proteins into cells biotechnology or nanotechnology? And since genes have
genetic memory, might this also be a form of information technology? The answer is probably
‘all of the above’. The important point is that the integration of these technologies and their
manipulation at the molecular and sub-molecular level will over the next decade provide major
advances across many existing industries and create whole new industries.
3.1 A material perspective
On of the fundamental concept which is the ground basis for nanotechnology is the material
perspective. Before the advent of nanotechnology material was not seen atomically. Scientists
started decomposing large materials to from new components from them. it has been observed
that decomposition of a materials at nano scale changes its properties. For example scanning
tunneling microscopy. Number of mechanical and physical phenomena which appears when
system size is decreased these affects are known as mechanical effect or quantum size effects.
Where as the electronic characteristics of solids are altered with great decrease in particle size.
This effect does not come into play by going from macro to micro dimensions of materials. but
when micro to macro size reduction was performed this affect become dominant when molecular
size of the particle is reached. Electrical, optical, and magnetic properties of the materials
changed at nanoscale rearrangements
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8. 3.2 Nano Mechanics and bio materials.
The concept of nanomechanics was also originated when new chemical properties of conductors
and semi conductors were found. Nano materials empowered the production of new devices but
at the same time it also opened the potential risks in their reactions with biomaterials. Materials
exhibit different properties as they exhibited at macro level which enabled unique applications to
take place for example opaque elements become transparent such as copper, insulators become
conductor at nano scale treatment like silicon, solid can be converted into liquid at normal room
temperature such as gold. Bottom line is that nanotechnology totally transformed the entire
structure of any substance into new architecture.
3.3 Molecular perspective (simple to Complex)
Advanced chemistry has reached the level where it can produce molecules for almost every
structure of the present world. these techniques are used to prepare wide range of chemical
compounds such as polymers and pharmaceuticals but the extension of the control gives birth to
the question that how these molecules could be reassemble into more advanced super molecular
assemblies. Molecular self assembly in gradually evolving into supramolecular chemistry to
make the new components which can reassembles themselves.
3.4 Molecular Recognition
Another important concept is the molecular recognition which is one of the fundamental
concepts of nanotechnology. Molecular rearranges them selves chemically by molecular
recognition. There is special force that is present between molecules non covalent intermolecular
force which supports the conformation of chemical similarity of molecules.
Chapter 4
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9. Tools In Nanotechnology
The main tools used in nanotechnology are three main microscopes:-
(i) Transmission Electron Microscope (TEM)
(ii) Atomic Force Microscope (AFM)
(iii) Scanning Tunneling Microscope (STM)
4.1 Transmission Electron Microscope (TEM)
The transmission electron microscope is one that utilizes a high-energy electron beam that
probes sample materials with a thickness less than 100 nanometers (nm). While some electrons
are either absorbed or bounced of the material, others pass through it creating a magnified image
as the one shown in the example. Current TEMs use digital cameras placed behind the material
to capture and record images, magnifying images up to 30 million times. The TEM is the most
popular microscope used the make images published in scientific journals on nanocrystals found
in semiconductors.
4.2 Atomic Force Microscope (AFM)
The atomic force microscope (AFM) uses a small silicon tip as a probe to make images of
sample material. While the probe move along the surface of the sample, the electrons of the
atoms in the material begin to repel the electrons of the probe. The AFM then adjusts the height
of the probe to keep the force of the sample constant. A mechanism records the movement of the
probe and sends this information to a computer that will generate a three-dimensional image as
shown in the slide. The image will show the exact topography of the surface.
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10. 4.3 Scanning Tunneling Microscope (STM)
A scanning tunneling microscope (STM) uses a wavelike property of electrons known as
tunneling, which allows electrons emitted from a probe to penetrate, or tunnel into, the surface of
the examined object. The electrons generate a tiny electric current that the STM measures.
Similar to the atomic force microscope, the height of the probe in the STM is adjusted constantly
to keep the current constant. In doing, so a detailed map of the material’ surface is produced as
the example in this slide shows.
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11. Chapter 5
Nanotechnology Applications
Nanotechnology opens the way towards new production routes, towards new, more
efficient, performance and intelligent materials, towards new design of structures and
related monitoring and maintenance systems.
The various applications of nanotechnology in different fields are as follows:-
(i) Computing and Data Storage
(ii) Materials and Manufacturing
(iii) Health and Medicine
(iv) Energy and Environment
(v) Space Exploration
5.1 Computing and Data Storage
As the ever-increasing power of computer chips brings us closer and closer to the limits of
silicon technology, many researchers are betting that the future will belong to “spintronics”: a
nanoscale technology in which information is carried not by the electron’s charge, as it is in
conventional microchips, but by the electron’s intrinsic spin. If a reliable way can be found to
control and manipulate the spins, these researchers argue, spintronic devices could offer higher
data processing speeds, lower electric consumption, and many other advantages over
conventional chips–including, perhaps, the ability to carry out radically new quantum
computations.
Now, University of Notre Dame physicist Boldizsar Janko and his colleagues believe they have
found such a control technique. Their work, funded by the National Science Foundation through
a Nanoscale Interdisciplinary Research Team grant, was published in the March 5, 2005, edition
of the journal Nature.
The idea is to create the device as a series of layers, each only a few dozen nanometers thick. At
the base is a layer of diluted magnetic semiconductor, a type of material Janko and his group
have been studying intensively. When gallium arsenide is doped with manganese atoms, for
example, each manganese atom contributes an extra electron, and thus an extra electron spin; the
result is a semiconductor material that can be magnetized in much the same way as iron. Then an
insulator material is layered over the base, followed by a layer of superconducting material.
Next, a magnetic field is applied perpendicular to the top surface (see animation above). Thanks
to the basic physics of superconductors, the field can make it through only by pinching itself
down into an array of nanoscale flux tubes. That super concentrates the field inside each tube, so
that it creates a spot of high-intensity magnetism on the semiconductor layer below, which, in
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12. turn, creates a patch of closely aligned electron spins. The resulting spin patches, one for each
flux tube, are then available for encoding information.
The effect resembles what happens when you sprinkle iron filings on a piece of paper, and then
hold a bar magnet underneath, says Janko: the presence of the magnet (the flux tube) makes the
iron filings (the spins) stand at attention. Furthermore, he says, just as you can manipulate the
filings by moving the magnet underneath the paper, you can manipulate the spins in this system
by moving the flux tubes. For example, an electric current flowing through the superconductor
will cause a given flux tube to move to one side (with the patch of spins underneath moving
along with it), while a current flowing in the reverse direction will move it back to the other side
(see animation, this video requires the free RealPlayer plug-in).
5.2 Materials and Manufacturing
The Nanotechnology, Advanced Materials and Manufacturing (NM) topic addresses innovations
and development of new materials, devices, machines, structures and manufacturing processes
for the advancement of the competitive nature. NM includes materials and manufacturing
technologies such as electronic materials and processes, high temperature materials, structural
materials, coatings, composites, powder processing, nanomanufacturing, printing, patterning and
lithography, machining, casting, joining, additive manufacturing, self-assembly, and other
related research areas.
The NM program seeks to support high-risk, high-payoff innovative technologies with the
potential for large impact on business, consumers, and society, thereby catalyzing new business
opportunities for small businesses in today's global marketplace. NSF is committed to supporting
scientific discoveries to benefit society and to emphasize private sector commercialization.
Novel technologies aimed at achieving increased performance, reduced cost, and/or new
functions or applications are of great interest.
5.3 Health and Medicine
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13. Nanomedicine: NBM is an international, peer-reviewed journal presenting novel, significant,
and interdisciplinary theoretical and experimental results related to nanoscience and
nanotechnology in the life sciences. Content includes basic, translational, and clinical research
addressing diagnosis, treatment, monitoring, prediction, and prevention of diseases. In addition
to bimonthly issues, the journal website (click here) also presents important nanomedicine-
related information, such as future meetings, meeting summaries, funding opportunities, societal
subjects public health, and ethical issues of nanomedicin e .
The potential scope of nanomedicine is broad, and we expect it to eventually involve all aspects
of medicine. Sub-categories include synthesis, bioavailability, and biodistribution of
nanomedicines; delivery, pharmacodynamics, and pharmacokinetics of nanomedicines; imaging;
diagnostics; improved therapeutics; innovative biomaterials; interactions of nanomaterials with
cells, tissues, and living organisms; regenerative medicine; public health; toxicology; point of
care monitoring; nutrition; nanomedical devices; prosthetics; biomimetics; and bioinformatics.
5.4 Energy And Environment
Development of new energy technologies and technologies for a cleaner environment are two
important focus areas. For example, the development of light and strong new materials would
make planes, trains and cars lighter and thus reduce energy consumption. Development of
effective methods for the conversion of one type of energy to another is another important area.
Materials with new functional properties will be able to streamline the energy conversion, for
example from sunlight to electricity in solar cells, or from electrical energy to chemical energy in
the form of hydrogen gas. The production of new and effective nanomaterials will also provide
an environmental benefit because the material need will be less than with the use of traditional
materials.
Choosing the main profile of “Nanotechnology for materials, energy and environment” you will
contribute to the development of such new environmental friendly energy technologies. You will
also be able to contribute to the development of for example new, effective methods for
purifying gases, liquids and drinking water as well as separating CO2 for storage. In order to
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14. avoid possible negative effects, it is also crucial to understand the impact new nanomaterials will
have on the environment. A specialisation within “Nanotechnology for materials, energy and
environment”, will equip in facing the world's climate challenges.
5.5 Space Exploration
NASA and other researchers are exploring the use of carbon based Nanotubes to deliver
solutions for some of its most promising visions of space exploration. This includes such
applications as a huge space elevator which can carry cargo to and from earth without the need
for orbital takeoff and landing. Nanotechnology is also being considered for other applications as
well, such as solar sail applications that can be used to propel spacecraft using light from the sun,
ion thrusters that replace chemical rockets, and materials that can be used to make the outside of
spacecraft resilient to bombardment from space debris.
The great space elevator concept has been the subject of much fascination and imagination,
and it no doubt faces a host of engineering challenges. The idea is to create a long cable from the
Earth to space, tethering the cable to an object in orbit—such as an asteroid in space—and
anchoring it on Earth to a station that is rigged in the ocean somewhere. Cargo can then be
shuttled back and forth without the need for rockets and fuel as the transport mechanism. The
cable would extend to 90,000 kilometers in length, be constructed of carbon based Nanotubes,
and use solar power to generate the electricity needed to shuttle it back and forth from space.
NASA’s Institutes for Advanced Concepts and the Elevator 2010 group provide insights and
yearly competitions to accelerate the time to production of the first successful prototype.
Nanotechnology is also being considered for use with space craft as well. One such use comes
in the form of solar sails. These use electricity from the sun to power a spacecraft’s travels,
rather than relying on thruster engines. Researchers have used carbon based Nanotubes to create
the thin sheets used as the space sails. And to replace chemical rockets altogether, ion thrusters
can use solar cells to generate electric fields as the propulsion mechanism. Additionally, other
researchers have explored the possibility of using Nanotubes for the exterior of the spaceship
itself, to create a resilient exterior that can withstand space debris bombardment. Ultimately, it
will even be possible to use Nanoparticles to effect any necessary repairs to the ship’s hull.
Chapter 6
Exciting Applications of Nanotechnology
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15. 6.1 Nanopowders – building blocks of nanomaterials
Nanopowders contain particles less than 100 nm in size — 1/10,000th the thickness of a human
hair. The physical, chemical and biological properties of such small particles allow industry to
incorporate enhanced functionalities into products.
Some of the unique properties of interest to industry are enhanced transparency from particles
being smaller than the wavelength of visible light, and high surface areas for enhanced
performance in surface area-driven reactions such as catalysts and drug solubilisation.
These unique properties give rise to a range of new and improved materials with a breadth of
applications. For example, nanotechnology allows plastics to retain transparency while also
taking on characteristics such as resistance to abrasion, conductivity or UV protection found in
ceramics or metals. New medical nanomaterials are being developed, such as synthetic bone and
bone cement, as well as drugs with improved solubility to allow lower dosing, more efficient
drug delivery and fewer adverse side effects.
The high surface areas of nanoparticles are being exploited by industry in catalysts that improve
chemical reactions in applications such as cleaning up car exhausts and potentially to remove
toxins from the environment. For example, petroleum and chemical processing companies are
using nanostructured catalysts to remove pollutants — $30 billion industry in 1999 with the
potential of $100 billion per year by 2015. Improved catalysts illustrate that improvements to
existing technology can open up whole new markets — nanostructured catalysts look likely to be
a critical component in finally making fuel cells a reality, which could transform our power
generation and distribution industry.
6.2 Membranes
Nanotechnology can address one of the most pressing issues of the 21st Century — safe, clean
and affordable water. There are 1.3 billion people without access to safe drinking water and
15
16. indications are that global consumption of water will likely double in the next 20 years. Fresh
water supplies are already limiting the growth of our cities — Australian cities such as
Sydney and Perth are considering waste water reuse schemes to augment their water supplies,
London is investing ₤200 million in desalination and Singapore recycles wastewater. Further
technology development is required to make this cost effective and allow it to become a more
mainstream water supply option.
Nanomembrane filtration devices that ‘clean’ polluted water, sifting out bacteria, viruses, heavy
metals and organic material, are being explored by research teams in the US, Israel and Australia
(at the UNESCO Centre for Membrane Science and Technology at the University of New South
Wales and a consortium of CSIRO Divisions). The key to lowering the energy demand and
improving throughput for desalination is in understanding how to selectively separate small
molecules, and package these technologies for exploitation. Separation of molecules occurs
efficiently in nature through membranes, such as the ion channels that remove salt from blood
and the respiratory membranes that transport oxygen and carbon dioxide. In order to reduce the
energy requirement for this process, nature provides large surface areas for the transport of
molecules. A parallel approach is being developed by nanotechnologists for the production of
nanoarchitectures for cost-effective filtration systems in large-scale water purification.
6.3 Carbon Nanotube
Carbon nanotubes possess many unique properties which make them ideal AFM probes. Their
high aspect ratio provides faithful imaging of deep trenches, while good resolution is retained
16
17. due to their nanometer-scale diameter. These geometrical factors also lead to reduced tip-sample
adhesion, which allows gentler imaging. Nanotubes elastically buckle rather than break when
deformed, which results in highly robust probes. They are electrically conductive, which allows
their use in STM and EFM (electric force microscopy), and they can be modified at their ends
with specific chemical or biological groups for high resolution functional imaging. Professor
Charles M. Lieber Group
CNT exhibits extraordinary mechanical properties: the Young's modulus is over 1 Tera Pascal. It
is stiff as diamond. The estimated tensile strength is 200 Giga Pascal. These properties are ideal
for reinforced composites, nanoelectromechanical systems (NEMS)
Carbon Nanotube Transistors exploit the fact that nm- scale nanotubes (NT) are ready-made
molecular wires and can be rendered into a conducting, semiconducting, or insulating state,
which make them valuable for future nanocomputer design. Carbon nanotubes are quite popular
now for their prospective electrical, thermal, and even selective-chemistry applications. Physics
News 590, May 21, 2002
Many potential applications have been proposed for carbon nanotubes, including conductive and
high-strength composites; energy storage and energy conversion devices; sensors; field emission
displays and radiation sources; hydrogen storage media; and nanometer-sized semiconductor
devices, probes, and interconnect. Some of these applications are now realized in products.
Others are demonstrated in early to advanced devices, and one, hydrogen storage, is clouded by
controversy. Nanotube cost, polydispersity in nanotube type, and limitations in processing and
assembly methods are important barriers for some applications of single-walled nanotubes.
6.4 Molecular electronics — cross bar latches to replace silicon chips
Hewlett-Packard — one of the world's biggest computer companies — declared on 1 February
2005 that it is on the verge of a revolution in computer chip technology10. They believe that
silicon computer chips will have reached a technical dead end in about a decade, to be replaced
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18. by tiny nanotechnology devices described as ‘cross bar latches’. These molecular-scale
alternatives to the transistor should dramatically improve the performance of computers because
they are much smaller — only 2 or 3 nm in size compared with 90 nm for transistors — and they
can store memory for much longer periods.
The new device consists of a wire that is crossed by two other wires. The resulting junctions
serve as switches that are only a few atoms across and can be programmed by a repeatable set of
electrical pulses.
6.5 Quantum Computers
The quantum computer uses quantum particles as the "tape" in the Turing experiment. Because
the presence of a symbol or a blank in the Turing tape symbolizes the binary digits, so can the
state of the quantum particles be used to hold these values. The use of multiple quantum particles
also means that the quantum computer will be much faster than the Turing machine since it can
perform several calculations simultaneously.
Moreover, unlike today's computers that uses the basic bit which has only two states (1 or 0), a
quantum computer will store information as quantum bits which can hold more than two values.
This ability of qubits to exist in more than two states means that a quantum computer has the
capability of performing more than a million simultaneous computations at one time and the
potential to be a lot faster and a lot more powerful than today's supercomputers.
Quantum computers will also be able to utilize one other important characteristic of quantum
particles known as entanglement. The property of entanglement makes it possible to assign and
determine the value or the spin of a quantum particle by introducing an outside force.
6.6 NanoRobotics
Basic nanomachines are already in use.
Nanobots will be the next generation of nanomachines. Advanced nanobots will be able to sense
and adapt to environmental stimuli such as heat, light, sounds, surface textures, and chemicals;
perform complex calculations; move, communicate, and work together; conduct molecular
assembly; and, to some extent, repair or even replicate themselves. Nanobot.info is an
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19. informational site that provides information on both recent developments and future applications
at the intersection of nanotechnology and robotics. Nanotechnology is the science and
application of creating objects on a level smaller than 100 nanometers. The extreme concept of
nanotechnology is the "bottom up" creation of virtually any material or object by assembling one
atom at a time. Although nanotech processes occur at the scale of nanometers, the materials and
objects that result from these processes can be much larger. Large-scale results happen when
nanotechnology involves massive parallelism in which many simultaneous and synergistic
nanoscale processes combine to produce a large-scale result.
Conclusion
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20. Nanotechnology offers the ability to build large numbers of products that are incredibly powerful
by today's standards. This possibility creates both opportunity and risk. The problem of
minimizing the risk is not simple; excessive restriction creates black markets, which in this
context implies unrestricted nanofabrication. Selecting the proper level of restriction is likely to
pose a difficult challenge.
This paper describes a system that allows the risk to be dealt with on two separate fronts: control
of the molecular manufacturing capacity, and control of the products. Such a system has many
advantages. A well-controlled manufacturing system can be widely deployed, allowing
distributed, cheap, high-volume manufacturing of useful products and even a degree of
distributed innovation. The range of possible nanotechnology-built products is almost infinite.
Even if allowable products were restricted to a small subset of possible designs, it would still
allow an explosion of creativity and functionality.
Preventing a personal nanofactory from building unapproved products can be done using
technologies already in use today. It appears that the nanofactory control structure can be made
virtually unbreakable. Product approval, by contrast, depends to some extent on human
institutions. With a block-based design system, many products can be assessed for degree of
danger without the need for human intervention; this reduces subjectivity and delay, and allows
people to focus on the few truly risky designs.
In addition to preventing the creation of unrestricted molecular manufacturing devices, further
regulation will be necessary to preserve the interests of existing commercial and military
institutions. For example, the effects of networked computers on intellectual property rights have
created concern in several industries, and the ability to fabricate anything will surely increase the
problem. National security will demand limits on the weapons that can be produced.
References
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