Tag Archives: nanocomputer

Molecular Nanocomputers

Computer scientists at Caltech have designed DNA molecules that can carry out reprogrammable computations, for the first time creating so-called algorithmic self-assembly in which the same “hardware” can be configured to run differentsoftware.”

A team headed by Caltech‘s Erik Winfree (PhD ’98), professor of computer science, computation and neural systems, and bioengineering, showed how the DNA computations could execute six-bit algorithms that perform simple tasks. The system is analogous to a computer, but instead of using transistors and diodes, it uses molecules to represent a six-bit binary number (for example, 011001) as input, during computation, and as output. One such algorithm determines whether the number of 1-bits in the input is odd or even, (the example above would be odd, since it has three 1-bits); while another determines whether the input is a palindrome; and yet another generates random numbers.

Think of them as nano apps,” says Damien Woods, professor of computer science at Maynooth University near Dublin, Ireland, and one of two lead authors of the study. “The ability to run any type of software program without having to change the hardware is what allowed computers to become so useful. We are implementing that idea in molecules, essentially embedding an algorithm within chemistry to control chemical processes.”

The system works by self-assembly: small, specially designed DNA strands stick together to build a logic circuit while simultaneously executing the circuit algorithm. Starting with the original six bits that represent the input, the system adds row after row of molecules—progressively running the algorithm. Modern digital electronic computers use electricity flowing through circuits to manipulate information; here, the rows of DNA strands sticking together perform the computation. The end result is a test tube filled with billions of completed algorithms, each one resembling a knitted scarf of DNA, representing a readout of the computation. The pattern on each “scarf” gives you the solution to the algorithm that you were running. The system can be reprogrammed to run a different algorithm by simply selecting a different subset of strands from the roughly 700 that constitute the system.

We were surprised by the versatility of programs we were able to design, despite being limited to six-bit inputs,” says David Doty, fellow lead author and assistant professor of computer science at the University of California, Davis. “When we began experiments, we had only designed three programs. But once we started using the system, we realized just how much potential it has. It was the same excitement we felt the first time we programmed a computer, and we became intensely curious about what else these strands could do. By the end, we had designed and run a total of 21 circuits.”

The findings have been reported in the journal Nature.

Source: https://www.caltech.edu/

Nanorobots Deliver Drugs Directly To Diseased Tissue

Scientists at EPFL and ETH Zurich in Switzerland have developed tiny elastic robots that can change shape depending on their surroundings. Modeled after bacteria and fully biocompatible, these robots optimize their movements so as to get to hard-to-reach areas of the human body. They stand to revolutionize targeted drug delivery.

One day we may be able to ingest tiny robots that deliver drugs directly to diseased tissue, thanks to research being carried out at EPFL and ETH Zurich.

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The robots are modeled after bacteria and fully biocompatible© 2019 EPFL/ ETHZ

The group of scientists – led by Selman Sakar at EPFL and Bradley Nelson at ETH Zurich – drew inspiration from bacteria to design smart, biocompatible microrobots that are highly flexible. Because these devices are able to swim through fluids and modify their shape when needed, they can pass through narrow blood vessels and intricate systems without compromising on speed or maneuverability. They are made of hydrogel nanocomposites that contain magnetic nanoparticles allowing them to be controlled via an electromagnetic field.

In an article appearing in Science Advances, the scientists describe the method they have developed for “programming the robot’s shape so that it can easily travel through fluids that are dense, viscous or moving at rapid speeds. When we think of robots, we generally think of bulky machines equipped with complex systems of electronics, sensors, batteries and actuators. But on a microscopic scale, robots are entirely different.

Fabricating miniaturized robots presents a host of challenges, which the scientists addressed using an origami-based folding method. Their novel locomotion strategy employs embodied intelligence, which is an alternative to the classical computation paradigm that is performed by embedded electronic systems.Our robots have a special composition and structure that allow them to adapt to the characteristics of the fluid they are moving through. For instance, if they encounter a change in viscosity or osmotic concentration, they modify their shape to maintain their speed and maneuverability without losing control of the direction of motion,” says Sakar.

These deformations can be “programmed” in advance so as to maximize performance without the use of cumbersome sensors or actuators. The robots can be either controlled using an electromagnetic field or left to navigate on their own through cavities by utilizing fluid flow. Either way, they will automatically morph into the most efficient shape.

Source: https://actu.epfl.ch/

New Material For New Processor

Computers used to take up entire rooms. Today, a two-pound laptop can slide effortlessly into a backpack. But that wouldn’t have been possible without the creation of new, smaller processors — which are only possible with the innovation of new materials. But how do materials scientists actually invent new materials? Through experimentation, explains Sanket Deshmukh, an assistant professor in the chemical engineering department of Virginia Tech whose team’s recently published computational research might vastly improve the efficiency and costs savings of the material design process.

Deshmukh’s lab, the Computational Design of Hybrid Materials lab, is devoted to understanding and simulating the ways molecules move and interact — crucial to creating a new material. In recent years, materials scientists have employed machine learning, a powerful subset of artificial intelligence, to accelerate the discovery of new materials through computer simulations. Deshmukh and his team have recently published research in the Journal of Physical Chemistry Letters demonstrating a novel machine learning framework that trainson the fly,” meaning it instantaneously processes data and learns from it to accelerate the development of computational models. Traditionally the development of computational models are “carried out manually via trial-and-error approach, which is very expensive and inefficient, and is a labor-intensive task,” Deshmukh explained.

This novel framework not only uses the machine learning in a unique fashion for the first time,” Deshmukh said, “but it also dramatically accelerates the development of accurate computational models of materials.” “We train the machine learning model in a ‘reverse’ fashion by using the properties of a model obtained from molecular dynamics simulations as an input for the machine learning model, and using the input parameters used in molecular dynamics simulations as an output for the machine learning model,” said Karteek Bejagam, a post-doctoral researcher in Deshmukh’s lab and one of the lead authors of the study.

This new framework allows researchers to perform optimization of computational models, at unusually faster speed, until they reach the desired properties of a new material.

Source: https://vtnews.vt.edu/

NanoComputers Could Run a Million Times Faster

Transition metal dichalcogenides (TMDCs) possess optical properties that could be used to make computers run a million times faster and store information a million times more energy-efficiently, according to a study led by Georgia State University.

Computers operate on the time scale of a fraction of a nanosecond, but the researchers suggest constructing computers on the basis of TMDCs, atomically thin semiconductors, could make them run on the femtosecond time scale, a million times faster. This would also increase computer memory speed by a millionfold.

There is nothing faster, except light,” said Dr. Mark Stockman, lead author of the study and director of the Center for Nano-Optics and a Regents’ Professor in the Department of Physics and Astronomy at Georgia State. “The only way to build much faster computers is to use optics, not electronics. Electronics, which is used by current computers, can’t go any faster, which is why engineers have been increasing the number of processors. We propose the TMDCs to make computers a million times more efficient. This is a fundamentally different approach to information technology.”

The researchers propose a theory that TMDCs have the potential to process information within a couple of femtoseconds. A femtosecond is one millionth of one billionth of a second. A TMDC has a hexagonal lattice structure that consists of a layer of transition metal atoms sandwiched between two layers of chalcogen atoms. This hexagonal structure aids in the computer processor speed and also enables more efficient information storage. The TMDCs have a number of positive qualities, including being stable, non-toxic, thin, light and mechanically strong. Examples include molybdenum disulfide (MOS2) and tungsten diselenide (WSe2). TMDCs are part of a large family called 2D materials, which is named after their extraordinary thinness of one or a few atoms. In this study, the researchers also established the optical properties of the TMDCs, which allow them to be ultrafast.

The findings are published in the journal Physical Review B.

Source: https://news.gsu.edu/

Quantum Computer Controls One Billion Electrons Per Second One-by-One.

University of Adelaide-led research in Australia has moved the world one step closer to reliable, high-performance quantum computing. An international team has developed a ground-breaking single-electronpump”. The electron pump device developed by the researchers can produce one billion electrons per second and uses quantum mechanics to control them one-by-one. And it’s so precise they have been able to use this device to measure the limitations of current electronics equipment. This paves the way for future quantum information processing applications, including in defence, cybersecurity and encryption, and big data analysis.

This research puts us one step closer to the holy grail – reliable, high-performance quantum computing,” says project leader Dr Giuseppe C. Tettamanzi, Senior Research Fellow, at the University of Adelaide’s Institute for Photonics and Advanced Sensing.

Published in the journal Nano Letters, the researchers also report observations of electron behaviour that’s never been seen before – a key finding for those around the world working on quantum computing.

Quantum computing, or more broadly quantum information processing, will allow us to solve problems that just won’t be possible under classical computing systems,” says Dr Tettamanzi. “It operates at a scale that’s close to an atom and, at this scale, normal physics goes out the window and quantum mechanics comes into play.  To indicate its potential computational power, conventional computing works on instructions and data written in a series of 1s and 0s – think about it as a series of on and off switches; in quantum computing every possible value between 0 and 1 is available. We can then increase exponentially the number of calculations that can be done simultaneously.”

Source: https://www.adelaide.edu.au/

Nanoparticles Fom Tea Leaves Destroy 80% Of Lung Cancer Cells

Nanoparticles derived from tea leaves inhibit the growth of lung cancer cells, destroying up to 80% of them, new research by a joint Swansea University (UK) and Indian team has shown. The team made the discovery while they were testing out a new method of producing a type of nanoparticle called quantum dots.  These are tiny particles which measure less than 10 nanometres.  A human hair is 40,000 nanometres thick.

Although nanoparticles are already used in healthcare, quantum dots have only recently attracted researchers’ attention.  Already they are showing promise for use in different applications, from computers and solar cells to tumour imaging and treating cancerQuantum dots can be made chemically, but this is complicated and expensive and has toxic side effects.  The Swansea-led research team were therefore exploring a non-toxic plant-based alternative method of producing the dots, using tea leaf extract.

Tea leaves contain a wide variety of compounds, including polyphenols, amino acids, vitamins and antioxidants.   The researchers mixed tea leaf extract with cadmium sulphate (CdSO4) and sodium sulphide (Na2S) and allowed the solution to incubate, a process which causes quantum dots to form.   They then applied the dots to lung cancer cells. Tea leaves are a simpler, cheaper and less toxic method of producing quantum dots, compared with using chemicals, confirming the results of other research in the field. Quantum dots produced from tea leaves inhibit the growth of lung cancer cells.  They penetrated into the nanopores of the cancer cells and destroyed up to 80% of them.  This was a brand new finding, and came as a surprise to the team.

The research, published in “Applied Nano Materials”, is a collaborative venture between Swansea University experts and colleagues from two Indian universities.

Source: http://www.swansea.ac.uk/

Strain Improves Performance of Atomically Thin Semiconductor

Researchers in UConn’s Institute of Materials Science significantly improved the performance of an atomically thin semiconductor material by stretching it, an accomplishment that could prove beneficial to engineers designing the next generation of flexible electronics, nano devices, and optical sensors.

In a study appearing in the research journal Nano Letters, Michael Pettes, assistant professor of mechanical engineering, reports that a six-atom thick bilayer of tungsten diselenide exhibited a 100-fold increase in photoluminescence when it was subjected to strain. The material had never exhibited such photoluminescence before.

The findings mark the first time scientists have been able to conclusively show that the properties of atomically thin materials can be mechanically manipulated to enhance their performance, Pettes says. Such capabilities could lead to faster computer processors and more efficient sensors.

The process the researchers used to achieve the outcome is also significant in that it offers a reliable new methodology for measuring the impact of strain on ultrathin materials, something that has been difficult to do and a hindrance to innovation.

Experiments involving strain are often criticized since the strain experienced by these atomically thin materials is difficult to determine and often speculated as being incorrect,” says Pettes. “Our study provides a new methodology for conducting strain-dependent measurements of ultrathin materials, and this is important because strain is predicted to offer orders of magnitude changes in the properties of these materials across many different scientific fields.”

Source: https://today.uconn.edu/