What is Molecular Computing:

Molecular computing is a generic term for any computational scheme which uses individual atoms or molecules as a means of solving computational problems. Molecular computing is most frequently associated with DNA computing, because that has made the most progress, but it can also refer toquantum computingor molecular logic gates. All forms of molecular computing are currently in their infancy, but in the long run are likely to replace traditional silicon computers, which suffer barriers to higher levels of performance.A single kilogram of carbon contains 5 x 1025atoms. Imagine if we could use only 100 atoms to store a single bit or perform a computational operation. Using massive parallelism, a molecular computing weighing just a kilogram could process more than 1027operations per second, more than a billion times faster than todays best supercomputer, which operates at about 1017operations per second. With so much greater computational power, we could achieve feats of calculation and simulation unimaginable to us today.Different proposals for molecular computers vary in the principles of their operation. In DNA computing, DNA serves as the software whereas enzymes serve as the hardware. Custom-synthesized DNA strands are combined with enzymes in a test tube, and depending on the length of the resulting output strand, a solution can be derived. DNA computation is extremely powerful in its potential, but suffers from major drawbacks. DNA computation is non-universal, meaning that there are problems it cannot, even in principle, solve. It can only return yes-or-no answers to computational problems. In 2002, researchers in Israel created aDNA computerwhich could perform 330 trillion operations per second, more than 100,000 times faster than the speed of the fastest PC at the time.Anotherproposalfor molecular computing is quantum computing. Quantum computing takes advantage of quantum effects to perform computation, and the details are complicated. Quantum computing depends upon supercooled atoms locked in entangled states with one another. A major challenge is that as the number of computational elements (qubits) increases, it becomes progressively more difficult to insulate thequantum computerfrom matter on the outside, causing it to decohere, eliminating quantum effects and restoring the computer to a classical state. This ruins the calculation. Quantum computing may yet be developed into practical applications, but many physicists and computer scientists remain skeptical.An even more advanced molecular computer would involve nanoscale logic gates or nanoelectronic components conducting processing in a more conventional, universal, and controlled manner. Unfortunately, we currently lack the manufacturing capability necessary to fabricate such a computer. Nanoscale robotics capable of placing each atom in the desired configuration would be necessary to realize this type of molecular computer. Preliminary efforts to develop this type of robotics are underway, but a major breakthrough could take decades.

Another proposal formolecularcomputingis quantumcomputing. Quantumcomputingtakes advantage of quantum effects to perform computation, and the details are complicated.

The arrival of MNT would revolutionize wide sectors of human activity, including manufacturing, medicine, scientific research, communication,computing, and warfare. When full-blownmolecularnanotechnology will arrive is currently unknown, but some experts foresee its arrival sometime between 2010 and 2030.

Molecular ComputingImagine computers orders of magnitude more powerful and far cheaper than todays machines. Thats one promise of a field that uses individual molecules as microscopic switches. ByDavid Rotmanon May 1, 2000

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For Mark Reed, the future of molecular electronics has just arrived. A self-described device guy, Reed, who heads Yale Universitys electrical engineering department, prides himself on having a distinctly practical bent. Ask him about the possibility of one day using molecules to replace silicon in computers that are billions of times faster than todays PCs or that fit on the head of a pin, and he grimaces. I dont know how to do that. I dont think anyone does, he says dismissively.But that doesnt dim the excitement that Reed, a leading researcher in molecular electronics, is feeling. Using molecules synthesized by Rice University chemist James Tour, Reed has fabricated electronic memories and a simple logic element made up of molecules that function as tiny, individual switches. The devices, which rely on small organic molecules tailored by the Rice chemists to have just the right electronic properties, are crude laboratory experiments. But they work-the molecules acting as a component in ultrasmall electronic devices able to turn current on and off. Whats more, these early prototypes have already shown hints of performing memory and logic tricks not possible with silicon semiconductors.Most impressive, says Reed, is that the molecular devices are astonishingly easy-and potentially cheap-to make. You simply dip a silicon wafer lined with metal electrodes into a beaker filled with the right chemicals and give the molecules a few minutes to form on the electrodes. If youre clever enough with the chemistry, its possible to coax the molecules to spontaneously orient themselves on the electrodes. It works beautifully-and it works every time, says Reed.It may work every time, but theres considerable controversy about what these chemical reactions will ever amount to. While true believers envision a world in which microscopic molecular computers made at low cost perform remarkable calculations, skeptics think the field has lost sight of the real world of engineering limits. Meanwhile, device guys like Reed think the future-in the form of workable prototypes that can be integrated with conventional silicon technology-is now.The core advantage of molecular computing is the potential to pack vastly more circuitry onto a microchip than silicon will ever be capable of-and to do it cheaply. Semiconductor-makers can now cram about 28 million transistors on a chip by shrinking the smallest features of the transistors down to about 180 nanometers (billionths of a meter). Using conventional chip-making methods, however, the smaller you make a feature, the more expensive and difficult the process becomes. Many semiconductor experts doubt commercial fabrication methods can economically make silicon transistors much smaller than 100 nanometers. And even if chip-makers could figure out a reasonable way to etch them onto a chip, ultrasmall silicon components probably wouldnt work: At transistor dimensions of around 50 nanometers, the electrons begin to obey odd quantum laws, wandering where theyre not supposed to be.Molecules, on the other hand, are only a few nanometers in size, making possible chips containing billions-even trillions-of switches and components. In initial experiments, scientists have sandwiched a large number of molecules between metal electrodes. The devices work, however, because each molecule operates as a switch. If it were possible to wire a small number of molecules together as individual electronic components to form circuits, the result would change everything in computer design. Molecular memories could have a million times the storage density of todays best semiconductor chips, making it possible to store the experiences of a lifetime in a gadget the size of a wristwatch. Supercomputers could be small enough and cheap enough to incorporate into clothing. Worries that computing technology will soon hit a wall would disappear.Those applications are decades off-if they ever materialize. Still, Reed argues, some uses for molecular electronics could soon be feasible. Ultrasmall, cheap molecular devices could sit side-by-side with silicon, reducing the number of transistors and the power required by the circuit. This is something you could use today, something you could sell in Radio Shack, says Reed. This has a chance to totally change the economics of silicon.To make that a reality, Reed, Tour and chemists from Pennsylvania State University have co-founded a startup called Molecular Electronics. The group declines to say what the initial products will be, but Tour says having a working system in a couple years doesnt seem unrealistic.Until very recently, that prediction would have seemed far-fetched. But in the last year, the field has taken a leap from theory to the realm of the practical. Like their competitors at Yale and Rice, a West Coast collaboration of chemists and computer scientists from Hewlett-Packard and the University of California, Los Angeles, have recently characterized molecules capable of acting as electronic switches and memory (see past issue: Computing After Silicon, TR September/October 1999). R. Stanley Williams, who heads the effort at HP, says his team expects to build a prototype of a logic circuit that integrates a small number of nanoscale molecular devices within 18 months. We have the switches and wires-the components to actually make true nanocircuitry, says Williams.Molecular ComputingPage 2 of 4 ByDavid Rotmanon May 1, 2000

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The RecipeIn theory, at least, assembling a molecular electronic device is straightforward. In the version of the recipe favored by the HP/UCLA collaboration, the scientists first make a single monolayer of the right organic molecules in a chemical apparatus called a Langmuir trough; they then dip a silicon substrate covered by a pattern of metal electrodes into the trough. If the chemistry is just right, the molecules will bind to the metal electrodes, neatly orienting themselves. A second set of electrodes is then deposited on the molecules; the result is a monolayer of the organic molecules sandwiched between metal electrodes.The challenge is that most organic molecules are not electrical conductors at all-never mind having the electronic properties that let them work as an effective switch. What is needed to make the system function electronically are specially tailored molecules that turn on and off repeatedly in a reliable and detectable way (the properties that have made silicon so successful). Coming up with molecules able to do the trick is the domain of chemistry wizards like Rices Tour and UCLAs James Heath and Fraser Stoddart.Their wizardry began paying off in a big way last fall. First, the HP/UCLA group published a paper describing what is in effect a molecular fuse-a one-time switch based on a complex, dumbbell-shaped organic molecule called rotaxane; the scientists have subsequently made reversible switches. They also showed how the device could perform simple logic and memory functions. Within months the Yale/Rice collaboration rivaled that feat by describing the synthesis of other organic molecules that act as electronic devices.Despite the differences in molecular particulars, the two research groups are taking advantage of the same quantum effects that could eventually set fundamental limits on silicon semiconductors. The molecules separating the two electrodes would normally block the flow of current. In the nanoworld of individual molecules, however, electrons can tunnel through a barrier that, according to classical physics, should block their path. By manipulating a voltage placed across the electrodes, the scientists can adjust the tunneling rate and thus turn the current on or off.Reed has already started thinking of ways to use molecular devices in combination with conventional silicon. One type of quantum logic gate that Reed has recently built would, for example, do the same specialized function as seven much larger silicon transistors, significantly reducing the size and power consumption of an integrated circuit. And while fabricating conventional transistors requires complex and expensive processing, the molecular device can be glued on to the circuit, says Reed.Molecules could also provide ultra-cheap electronic memory with some attractive properties. The most common type of semiconductor memory is called DRAM, for dynamic random access memory. (This is the short-term memory your computer relies on when its running a program.) The problem with DRAM is that the stored information evaporates when the power is shut off-its volatile. Thats the reason you have to boot up Windows every time you turn your computer on, moving the program from your hard drive to the DRAM chips. But an experimental molecular device Reed made last fall holds data for more than 10 minutes after the power is shut off. Suppose we can get that up to several years, says Reed. It would essentially be nonvolatile memory. Imagine how many times you wouldnt have to boot up Windows.

Although these early applications are worlds away from the billion-transistor molecular computers that enthusiasts envision, they could show the value of organic molecules as an electronic material. They are a camels nose under the tent, says Reed, adding that these hybrid devices are already very realistic. Theyre the first step down the road to more complex [molecular] circuits.Its likely, however, to be a long road. Even a simple computer made of molecular components is at least a decade away-and then only if we get really clever, acknowledges Williams. But the HP chemist says his group is already on its way. In their initial prototypes, the California researchers have fabricated the top and bottom metal wires as perpendicular grids, creating a crossbar structure with the molecules sitting at the junctions of the wires. So far, the group has made devices with metal contacts that are thousands of nanometers in diameter; there are millions of molecules at each junction. But Williams says that by later this year the group expects to have wires measuring a few nanometers across. It didnt make sense to do everything hard right away. So we used much larger wires. Now were doing the experiments to switch to smaller wires and make the measurements.The nearly perfect candidates for such tiny wires are structures known as carbon nanotubes. These regularly shaped pipes, only a few nanometers in diameter, could be excellent conduits for electrons speeding through a molecular circuit. The problem is that nanotubes tend to form as a tangled mess-far from the neatly ordered arrays needed to fabricate complex circuits. Building any structures with nanotubes is now an art form, says physicist Paul McEuen of the University of California, Berkeley. We basically throw them down on the ground and look for [the structure] we want.The HP/UCLA group is confident theyll solve the wiring problem. Eventually nanotubes will be used. Their electronic and physical properties are so desirable, says Williams. For now, he says, the group is also working on silicon nanowires. And, promises Williams, with or without carbon nanotubes, by late summer the scientists will scale down the junctions of devices to smaller than 10 nanometers. The near-term targets are a 16-bit memory that is 100 nanometers on a side, and soon after that a similarly sized logic device. These rudimentary circuits may not threaten the reign of silicon, but they could be a milestone in helping prove that molecular electronics is feasible.But then comes the truly daunting part: turning these simple devices into complex logic circuits, and integrating them into an actual computer. One of the penalties you pay for making microelectronics based on chemistry is that, unlike silicon chips made in high-tech fabrication plants, molecular devices synthesized in vats of chemicals will inherently be full of defects. At the scale of individual molecules, chemistry is given to statistical fluctuations-sometimes it works and sometimes it doesnt. But its here that the HP/UCLA scientists contend they have made their most important breakthrough.Their answer: software that overcomes the defects. Several years ago, computer scientists at HP built a supercomputer called Teramac, using defective silicon chips so flawed they were considered worthless. The HP scientists cobbled these rejected chips into a computer by developing a crossbar architecture that makes it possible to connect any input with any output. Once the hardware was built, the computer was programmed to identify and route around any defects. The system worked-and its massive parallelism provided an archetype that the California scientists plan to use for their molecular computer.A chemist working on a computer is a bizarre thing. You cant go to a chemist and ask them to build a computer, says Heath, one of the UCLA scientists who is helping to synthesize the necessary components. But, he says, the Teramac architecture has provided the HP/UCLA group a clearly defined target. The software will turn it into a machine, says Heath. That molecular computer may be a long way off, he acknowledges. But theres no reason why it wont work.

The World BetweenWhile folks like Heath are sanguine, the technology has its share of doubters. The field of molecular electronics is in love with itself, says Rick Lytel, a computer scientist at Sun Microsystems. Despite his skepticism, however, Lytel is keeping a sharp eye on the field for Sun and is developing specifications to test and evaluate prototype molecular devices. He believes molecular electronics could eventually find uses as memory devices. But Lytel says many of his colleagues in the field have deluded themselves into thinking that they are only a step away from the marketplace.Even believers in the prospects of molecular electronics disagree with one another over the role the technology will play in computation and electronics. Take Mark Ratner, a chemist at Northwestern University who is generally regarded as one of the grandfathers of the field. Ratner doubts molecules will ever compete directly with silicon in complex computational tasks. You want to use molecules for what they do best and to compensate for where silicon falls short, says Ratner. In particular, he points to their ability to recognize and respond to other molecules. By combining those functions with the newly developed electronic properties, you might make tiny sensors and actuators that detect and react intelligently to biological and chemical clues. It might, says Ratner, make possible implantable biochips incorporating sensors and actuators made out of molecular electronics that sense the needs of the body and respond by discharging an appropriate dose of medication.For this pioneer of molecular electronics, the true potential of the field could be realized in bringing the world of microelectronics together with the world of biology and molecules. Molecular electronics, suggests Ratner, could be the piece of the puzzle that finally helps to bridge the material gap between biology and computing.Molecular SamplerOrganizationKey ResearchersFocusDelft University of Technology Cees Dekker Using carbon nanotubes as nanowires and electronic devices; has built a transistor out of a single nanotube Harvard University Charles Lieber Synthesizing arrays of carbon nanotubes that can act as both wires and electronic devices Hewlett-Packard/UCLA R. Stanley Williams, Philip Kuekes (HP); Fraser Stoddart, James Heath (UCLA) Chemically assembling arrays of reconfigurable switches for memory and logic; goal is to build a molecular computer IBM Research Phaedon Avouris Studying the properties of nanotubes; has made a transistor out of a single nanotube Rice University James Tour Developing a self-assembled computer with a highly interconnected network of logic and memory; has synthesized molecules with desirable properties University of Colorado Josef Michl Building a molecular computer; has made suitable molecules and short wires Yale University Mark Reed Collaborating with Rice University to build a molecular computer; has fabricated molecular switches and memory devices

Molecular Computing Elements:Gates and Flip-Flops

Licensing OpportunityCRADA OpportunityTDSchneider, PNHengen(NCI)Informal Description of the Invention:A completely molecular computer can be constructed using designed DNA and DNA binding proteins. Several versions of the device are possible. In the simplest device, bacteria or other cells are programmed with DNA sequences and DNA binding proteins that execute logical Boolean operations. It is also possible to construct molecular computers outside cells, but in this case special attention must be paid to providing energy to run the computer. The technology is based on the concept of a molecular flip-flop in which one or more proteins compete for binding to binding sites that overlap. Because only one protein can bind at a time but there are two ways for it to bind, the method can also be used to double the sensitivity of diagnostic assays.Formal Description of the Invention:The present invention is a method and apparatus for molecular computing which provides for molecular logic devices analogous to those of electronic computers, such as flip-flops, AND gates, etc. Coupling of the gates allows for molecular computing. The method allows data storage, the transformation of binary information and signal readout. Possible applications include encoding ``read only'' memory for microscopic identifiers, digital control of gene expression, and quantification of analytes. The computing elements also provide means for complex regulation of gene expression.

Molecular-Sized LEDs Provide the Basis for Molecular Computersfirst single-molecule LED

The tiny LED was created using a single polythiophene wire, an excellent electricity conductor already being used to make commercial LEDs. The wire was attached to the tip of a scanning tunneling microscope at one end and a gold surface at the other. Sending a current through the nanowire caused it to function as a light emitting diodebut only when the electrons traveled from the microscope to the gold surface. Reversing the polarity created only a negligible amount of light.

The molecular LED will give researchers a new way to explore phenomena on the quantum physics level and provides the first step toward creating molecule-sized parts that have both electronic and optical propertiescomponents that could serve as the building blocks for a molecular computer.

The ultimate challenge in the race to miniaturize light emitting diodes (LED) has now been met: a team led by the Institut de Physique et de Chimie des Matriaux de Strasbourg has developed the first ever single-molecule LED.The device is formed from a single polythiophene wire placed between the tip of a scanning tunneling microscope and agold surface. It emits light only when the current passes in a certain direction. This experimental tour de force sheds light on the interactions between electrons and photons at the smallest scales. Moreover, it represents yet another step towards creating components for a molecular computer in the future. This work has recently been published in the journalPhysical Review Letters.Light emitting diodes are components that emit light when an electric current passes through them and only let light through in one direction. LEDs play an important role in everyday life, as light indicators. They also have a promising future in the field of lighting, where they are progressively taking over the market. A major advantage of LEDs is that it is possible to make them very small, so point light sources can be obtained. With this in mind, one final miniaturization hurdle has recently been overcome by researchers at IPCMS in Strasbourg, in collaboration with a team from the Institut Parisien de Chimie Molculaire (CNRS): they have produced the first ever single-molecule LED.To achieve this, they used a single polythiophene wire. This substance is a good electricity conductor. It is made of hydrogen, carbon and sulfur, and is used to make larger LEDs that are already on the market. The polythiophene wire was attached at one end to the tip of ascanning tunneling microscope, and at the other end to a gold surface. The scientists recorded the light emitted when a current passed through this nanowire. They observed that the thiophene wire acts as alight emitting diode: light was only emitted when electrons went from the tip of the microscope towards the gold surface.. When the polarity was reversed, light emission was negligible.In collaboration with a theoretical team from the Service de Physique de l'Etat Condens, the researchers showed that this light was emitted when a negative charge (an electron) combined with a positive charge (a hole) in the nanowire and transmitted most of its energy to a photon. For every 100,000 electrons injected into the thiophene wire, a photon was emitted. Its wavelength was in the red range.From a fundamental viewpoint, this device gives researchers a new tool to probe phenomena that are produced when an electrical conductor emits light and it does so at a scale where quantum physics takes precedence over classical physics. Scientists will also be able to optimize substances to produce more powerful light emissions. Finally, this work is a first step towards making molecule-sized components that combine electronic and optical properties. Similar components could form the basis of a molecular computer.

Top 10 Inventions of 2014August 26, 2014-Technology-no comments

Aninventionsis a unique or novel device, method, composition or process.To change the time our world will also be changed . All of theinventionwill come to do some valuable things for human. NewInventionsmakes our life comfortable , easily to do something.It can effects inscience , cultural , technologyand every sector of the world.Cultural which is aninnovativeset of usefulsocial behavioursadopted by people and passed on to others.There areinventions thathavechangedourlives:Internet, mobile telephony,etc. All of them some are widely spread and come to our daily necessity. This are called the top of theworld.The top 10 inventions of the world are -The Driverless (Toy) Car :Driverless car is one of thegooglenew inventions.The cars carry sensors and running without driver works with this sensor technology. This car will come to the market in the latest of the year .

Driverless Toy CarSmart TV :Smart TVis one of the most latest technology in modern science . It is a such type of device , that access apps, browse the web and stream internet video from the internet. They are becoming more facility , more comfortable for the human. They are also a wide range of model.

smart tvSmart Fridge :Smart Firdgeis also known as internet Fridge . It has been programmed to sensed what products are being put into it and helps to determine when a product needs to be replenished .

smart firdgeSmart Computers with smell : Smart technologies will be available that will be able to detect information about your health just by smelling.Smart computers or smart phoneswill be able to tell one that he or she is going to catch cold even before his or her first sneeze.

Smart technologies : Future technology will smell.Latest invention: Flat Flexible Speaker:Aloudspeaker, which isless than 0.25mm thick, is thelatest invention in technologypresented by engineers fromUniversity of Warwick.The flexible speaker works bytransforming an electric signal into sound.The device is flexible and can be easily hung up a wall in an apartment or, due to its specific technique of producing sound.

latest-invention-flat-flexible-speakerWashing Machine That Doesnt Need Water :British companyXeroslooks forward to conquer the American market with itslatest invention, a newwashing systemable to save a lot of water usingnylon beads. New washing machine will save1.2 billion tons of water each year, which equals 17 million swimming pools.

water-less-wasing-machineEye-writer :This device was invented to help people bound to bed communicate.It allows people with one of neuromuscular syndromes to communicate with others by writing or drawing on the screen by tracking their eye movement and converting it to lines on a display.

eye-writer-top108. AbioCor Artificial Heart :A group of surgeons from Louisville, Kentucky managed to implant anew-generation artificial heartin a patien. Dubbed AbioCor, the device was implanted in a man who suffered from heart failure.

artificial-heart-abiocor-top10MicroMobile :Micromobile is one the greatest inventions of moders science. The marketing and the trade believe on the internet, each and everything is madecomputerized and automotivewhere micromobile is very important in this world.

mirrormobileSmart Glass :A company Vuzix fromRochester, New York, is bringing a new type of smart glass.This smart glasses are Internet-enabled and they allow do things such as reading email, using favorite apps, and receiving updates from sources like Facebook or other social sites .

ome scientists of Oxford University are developing a smart glass or smart eyewear device , to make thousands of blind people able to see.This smart glasses will have tiny cameras in the frame and pocket computers. This devices will warn the wearer of that smart eyewear device if any person or other objects in front of him.smart glasses or smart eyewear devicesRelated posts:he smart glasses will work using a pair of cameras. These cameras will determine the distance of objects and we simply translate that into a light display. For this the cameras will capture the information of objects covered by the eyesight of the user and will send it to the pocket sized mobile computer. That camera will be in the users pocket. The computer will then process the information and will simplify it into a certain pattern. These smart eyewear devices will also have light-emitting diodes (LED) in the lens. The information that the computer processed will then be sent to the lances. Then the LED on the lances will be lights up creating form of the pattern. This way this smart eyewear device will notify the user about the objects in front of him.