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Researchers at the NYU Tandon School of Engineering have pioneered a method for growing an atomic scale electronic material at the highest quality ever reported. In a paper published in Applied Physics Letters, Assistant Professor of Electrical and Computer Engineering Davood Shahrjerdi and doctoral student Abdullah Alharbi detail a technique for synthesizing large sheets of high-performing monolayer tungsten disulfide, a synthetic material with a wide range of electronic and optoelectronic applications.

“We developed a custom reactor for growing this material using a routine technique called chemical vapor deposition. We made some subtle and yet critical changes to improve the design of the reactor and the growth process itself, and we were thrilled to discover that we could produce the highest quality monolayer tungsten disulfide reported in the literature,” said Shahrjerdi. “It’s a critical step toward enabling the kind of research necessary for developing next-generation transistors, wearable electronics, and even flexible biomedical devices.”

The promise of two-dimensional electronic materials has tantalized researchers for more than a decade, since the first such material — graphene — was experimentally discovered. Also called “monolayer” materials, graphene and similar two-dimensional materials are a mere one atom in thickness, several hundred thousand times thinner than a sheet of paper. These materials boast major advantages over silicon — namely unmatched flexibility, strength, and conductivity — but developing practical applications for their use has been challenging.

Graphene (a single layer of carbon) has been explored for electronic switches (transistors), but its lack of an energy band gap poses difficulties for semiconductor applications. “You can’t turn off the graphene transistors,” explained Shahrjerdi. Unlike graphene, tungsten disulfide has a sizeable energy band gap. It also displays exciting new properties: When the number of atomic layers increases, the band gap becomes tunable, and at monolayer thickness it can strongly absorb and emit light, making it ideal for applications in optoelectronics, sensing, and flexible electronics.

Efforts to develop applications for monolayer materials are often plagued by imperfections in the material itself — impurities and structural disorders that can compromise the movement of charge carriers in the semiconductor (carrier mobility). Shahrjerdi and his student succeeded in reducing the structural disorders by omitting the growth promoters and using nitrogen as a carrier gas rather than a more common choice, argon.

Shahrjerdi noted that comprehensive testing of their material revealed the highest values recorded thus far for carrier mobility in monolayer tungsten disulfide. “It’s a very exciting development for those of us doing research in this field,” he said.

At electronica, imec, Holst Centre (set up by imec and TNO), and TNO have introduced their next-generation health patch. The small form-factor comfortable to wear health patch has been optimized for low power consumption and is the first of its kind to track physical and cardiac activity, while monitoring bioelectrical impedance. A key building block in the pursuit of improved and more accurate mobile health solutions, the patch is available for licensing by partner companies ready to initiate their own medical applications.

health patch

“Since our entry in this space, we’ve advanced far beyond proof-of-concept to a patch that has attained a high level of technical maturity,” says Ruben de Francisco, Program Manager Wearable Health at imec and Holst Centre, “The underlying technologies have been fully validated, and the patch itself has been tested within a controlled environment. Today, it is ready for preclinical and usability studies. Looking ahead, we plan to build on our expertise in the domain of data science to lay the foundation for a powerful patient management solution that not only captures data, but that also turns data into meaningful information upon which people and health providers can act.”

With more people living longer than ever before and chronic disease on the rise, traditional healthcare systems are being pushed to their limits. It is generally acknowledged that the concept of digital health, and specifically mobile health, can help address that issue by enabling individuals to better track and manage their health and receive personalized and optimized treatments while reducing medical inefficiencies and costs.

The health industry has recognized the challenges and solutions, with analysts predicting that the value of the global mobile health market is expected to more than triple in the next few years, from $19.2 billion in 2016 to $58.8 billion by 2020).

However, for mobile health solutions to be successful beyond concept, easy-to-use and accurate building blocks are required; technology that is being developed by imec, Holst Centre and TNO as part of their Wearable Health program. Their R&D on mobile health drives innovation from an application perspective, at system level and in terms of individual components – such as read-out circuits, batteries, adhesives, etc.

The health patch from imec, Holst Centre and TNO features more functionalities than any other patch, and does so in a small form-factor. At its heart is a chip that has been optimized for low power consumption. This chip is combined with a highly comfortable to wear electrode patch that can stay on the body for long periods of time, including when showering. It is the first patch to combine a variety of sensing capabilities – ranging from an accelerometer (to track a person’s physical activity) to ECG tracking (measuring the heart’s electrical activity) and bioelectrical impedance monitoring (measuring body composition, respiratory activity and the distribution of body fluids).

“Many companies working in the digital health realm have great ideas for innovative solutions that could make it easier to remotely monitor people suffering from heart and respiratory diseases, to give an example. However, what is typically lacking, are the devices on which to run these solutions,” comments Chris Van Hoof, Program Director Wearable Health at imec and Holst Centre. “When collaborating with Holst Centre, we help these companies to take the next steps, from concept to device, and our health patch is one of the many vehicles available for licensing and customized product development,” adds Jeroen van de Brand, Director flexible electronics at Holst Centre/TNO.

The health patch integrates unique technologies and components from industrial partners, including Hitachi Maxell’s batteries optimized for wearables, Shinko Electric Industries’ System in Package (SiP) miniaturization technology and Henkel’s adhesive and ink technology.

Scientists from the Semenov Institute of Chemical Physics of the Russian Academy of Sciences (ICP RAS) and the Moscow Institute of Physics and Technology (MIPT) have demonstrated that sensors based on binary metal oxide nanocomposites are sensitive enough to identify terrorist threats and detect environmental pollutants. The results of their study have been published in Sensors and Actuators B: Chemical.

This is a schematic representation of a binary sensor based on two metal oxides, with the nanoparticles of the catalytically active component (1) in yellow and the nanoparticles of the electron donor component (2) represented by the unshaded circles. Credit: the MIPT press office

This is a schematic representation of a binary sensor based on two metal oxides, with the nanoparticles of the catalytically active component (1) in yellow and the nanoparticles of the electron donor component (2) represented by the unshaded circles. Credit: the MIPT press office

Due to rapid industrial growth and the degradation of the environment, there is a growing need for the development of highly effective and selective sensors for pollutant detection. In addition, gas sensors could also be used to monitor potential terrorist threats.

“Choosing the right sensor composition can make a device at least ten times more effective and enable an exceptionally fast response, which is crucial for preventing terrorist attacks,” says Prof. Leonid Trakhtenberg of the Department of Molecular and Chemical Physics at MIPT, who is the leader of the research team and the head of the Laboratory of Functional Nanocomposites at ICP RAS.

According to the research findings, the most promising detection systems are binary metal oxide sensors, in which one component provides a high density of conductive electrons and another is a strong catalyst.

A mixed system of that kind has the two necessary components for effective gas detection, viz., an electron donor and a substance “accommodating” the reaction. An additional factor contributing to faster sensor response is the formation of chemisorption centers, i.e., the chemically active spots on the nanocrystals that facilitate gas molecule adsorption.

“We are planning further research into the possibilities for sensor design presented by the multicomponent metal oxide nanocomposites incorporating nanofibers. The development of new effective sensor compositions will be based on a reasonably balanced approach involving both the experimental tests and the advancement of our theoretical understanding of the sensing mechanisms,” comments Prof. Trakhtenberg.

A rather promising approach to the development of new gas detection systems is the use of “core-shell type” composite metal oxide nanofibers, where the “core” and the “shell” are composed of two different oxides.

A tiny machine


October 31, 2016

In 1959 renowned physicist Richard Feynman, in his talk “Plenty of Room at the Bottom,” spoke of a future in which tiny machines could perform huge feats. Like many forward-looking concepts, his molecule and atom-sized world remained for years in the realm of science fiction.

And then, scientists and other creative thinkers began to realize Feynman’s nanotechnological visions.

In the spirit of Feynman’s insight, and in response to the challenges he issued as a way to inspire scientific and engineering creativity, electrical and computer engineers at UC Santa Barbara have developed a design for a functional nanoscale computing device. The concept involves a dense, three-dimensional circuit operating on an unconventional type of logic that could, theoretically, be packed into a block no bigger than 50 nanometers on any side.

“Novel computing paradigms are needed to keep up with the demand for faster, smaller and more energy-efficient devices,” said Gina Adam, postdoctoral researcher at UCSB’s Department of Computer Science and lead author of the paper “Optimized stateful material implication logic for three dimensional data manipulation,” published in the journal Nano Research. “In a regular computer, data processing and memory storage are separated, which slows down computation. Processing data directly inside a three-dimensional memory structure would allow more data to be stored and processed much faster.”

While efforts to shrink computing devices have been ongoing for decades — in fact, Feynman’s challenges as he presented them in his 1959 talk have been met — scientists and engineers continue to carve out room at the bottom for even more advanced nanotechnology. A nanoscale 8-bit adder operating in 50-by-50-by-50 nanometer dimension, put forth as part of the current Feynman Grand Prize challenge by the Foresight Institute, has not yet been achieved. However, the continuing development and fabrication of progressively smaller components is bringing this virus-sized computing device closer to reality, said Dmitri Strukov, a UCSB professor of computer science.

“Our contribution is that we improved the specific features of that logic and designed it so it could be built in three dimensions,” he said.

Key to this development is the use of a logic system called material implication logic combined with memristors — circuit elements whose resistance depends on the most recent charges and the directions of those currents that have flowed through them. Unlike the conventional computing logic and circuitry found in our present computers and other devices, in this form of computing, logic operation and information storage happen simultaneously and locally. This greatly reduces the need for components and space typically used to perform logic operations and to move data back and forth between operation and memory storage. The result of the computation is immediately stored in a memory element, which prevents data loss in the event of power outages — a critical function in autonomous systems such as robotics.

In addition, the researchers reconfigured the traditionally two-dimensional architecture of the memristor into a three-dimensional block, which could then be stacked and packed into the space required to meet the Feynman Grand Prize Challenge.

“Previous groups show that individual blocks can be scaled to very small dimensions, let’s say 10-by-10 nanometers,” said Strukov, who worked at technology company Hewlett-Packard’s labs when they ramped up development of memristors and material implication logic. By applying those results to his group’s developments, he said, the challenge could easily be met.

The tiny memristors are being heavily researched in academia and in industry for their promising uses in memory storage and neuromorphic computing. While implementations of material implication logic are rather exotic and not yet mainstream, uses for it could pop up any time, particularly in energy scarce systems such as robotics and medical implants.

“Since this technology is still new, more research is needed to increase its reliability and lifetime and to demonstrate large scale three-dimensional circuits tightly packed in tens or hundreds of layers,” Adam said.

Robert Wolkow is no stranger to mastering the ultra-small and the ultra-fast. A pioneer in atomic-scale science with a Guinness World Record to boot (for a needle with a single atom at the point), Wolkow’s team, together with collaborators at the Max Plank Institute in Hamburg, have just released findings that detail how to create atomic switches for electricity, many times smaller than what is currently used.

Robert Wolkow, University of Alberta physics professor and the Principal Research Officer at Canada's National Institute for Nanotechnology, has developed a technique to switch a single-atom channel. Credit: John Ulan

Robert Wolkow, University of Alberta physics professor and the Principal Research Officer at Canada’s National Institute for Nanotechnology, has developed a technique to switch a single-atom channel. Credit: John Ulan

What does it all mean? With applications for practical systems like silicon semi-conductor electronics, it means smaller, more efficient, more energy-conserving computers, as just one example of the technology revolution that is unfolding right before our very eyes (if you can squint that hard).

“This is the first time anyone’s seen a switching of a single-atom channel,” explains Wolkow, a physics professor at the University of Alberta and the Principal Research Officer at Canada’s National Institute for Nanotechnology. “You’ve heard of a transistor–a switch for electricity–well, our switches are almost a hundred times smaller than the smallest on the market today.”

Today’s tiniest transistors operate at the 14 nanometer level, which still represents thousands of atoms. Wolkow’s and his team at the University of Alberta, NINT, and his spinoff QSi, have worked the technology down to just a few atoms. Since computers are simply a composition of many on/off switches, the findings point the way not only to ultra-efficient general purpose computing but also to a new path to quantum computing.

“We’re using this technology to make ultra-green, energy-conserving general purpose computers but also to further the development of quantum computers. We are building the most energy conserving electronics ever, consuming about a thousand times less power than today’s electronics.”

While the new tech is small, the potential societal, economic, and environmental impact of Wolkow’s discovery is very large. Today, our electronics consume several percent of the world’s electricity. As the size of the energy footprint of the digital economy increases, material and energy conservation is becoming increasingly important.

Wolkow says there are surprising benefits to being smaller, both for normal computers, and, for quantum computers too. “Quantum systems are characterized by their delicate hold on information. They’re ever so easily perturbed. Interestingly though, the smaller the system gets, the fewer upsets.” Therefore, Wolkow explains, you can create a system that is simultaneously amazingly small, using less material and churning through less energy, while holding onto information just right.

When the new technology is fully developed, it will lead to not only a smaller energy footprint but also more affordable systems for consumers. “It’s kind of amazing when everything comes together,” says Wolkow.

Wolkow is one of the few people in the world talking about atom-scale manufacturing and believes we are witnessing the beginning of the revolution to come. He and his team have been working with large-scale industry leader Lockheed Martin as the entry point to the market.

“It’s something you don’t even hear about yet, but atom-scale manufacturing is going to be world-changing. People think it’s not quite doable but, but we’re already making things out of atoms routinely. We aren’t doing it just because. We are doing it because the things we can make have ever more desirable properties. They’re not just smaller. They’re different and better. This is just the beginning of what will be at least a century of developments in atom-scale manufacturing, and it will be transformational.”

“Time Resolved Single Dopant Charge Dynamics in Silicon” appeared in the October 26 edition of Nature Communications, an open-access journal in the group of Nature, world-leading scientific publications.

Researchers have developed a prototype of a next-generation lithium-sulphur battery which takes its inspiration in part from the cells lining the human intestine. The batteries, if commercially developed, would have five times the energy density of the lithium-ion batteries used in smartphones and other electronics.

This is a computer visualization of villi-like battery material. Credit: Teng Zhao

This is a computer visualization of villi-like battery material. Credit: Teng Zhao

The new design, by researchers from the University of Cambridge, overcomes one of the key technical problems hindering the commercial development of lithium-sulphur batteries, by preventing the degradation of the battery caused by the loss of material within it. The results are reported in the journal Advanced Functional Materials.

Working with collaborators at the Beijing Institute of Technology, the Cambridge researchers based in Dr Vasant Kumar’s team in the Department of Materials Science and Metallurgy developed and tested a lightweight nanostructured material which resembles villi, the finger-like protrusions which line the small intestine. In the human body, villi are used to absorb the products of digestion and increase the surface area over which this process can take place.

In the new lithium-sulphur battery, a layer of material with a villi-like structure, made from tiny zinc oxide wires, is placed on the surface of one of the battery’s electrodes. This can trap fragments of the active material when they break off, keeping them electrochemically accessible and allowing the material to be reused.

“It’s a tiny thing, this layer, but it’s important,” said study co-author Dr Paul Coxon from Cambridge’s Department of Materials Science and Metallurgy. “This gets us a long way through the bottleneck which is preventing the development of better batteries.”

A typical lithium-ion battery is made of three separate components: an anode (negative electrode), a cathode (positive electrode) and an electrolyte in the middle. The most common materials for the anode and cathode are graphite and lithium cobalt oxide respectively, which both have layered structures. Positively-charged lithium ions move back and forth from the cathode, through the electrolyte and into the anode.

The crystal structure of the electrode materials determines how much energy can be squeezed into the battery. For example, due to the atomic structure of carbon, each carbon atom can take on six lithium ions, limiting the maximum capacity of the battery.

Sulphur and lithium react differently, via a multi-electron transfer mechanism meaning that elemental sulphur can offer a much higher theoretical capacity, resulting in a lithium-sulphur battery with much higher energy density. However, when the battery discharges, the lithium and sulphur interact and the ring-like sulphur molecules transform into chain-like structures, known as a poly-sulphides. As the battery undergoes several charge-discharge cycles, bits of the poly-sulphide can go into the electrolyte, so that over time the battery gradually loses active material.

The Cambridge researchers have created a functional layer which lies on top of the cathode and fixes the active material to a conductive framework so the active material can be reused. The layer is made up of tiny, one-dimensional zinc oxide nanowires grown on a scaffold. The concept was trialled using commercially-available nickel foam for support. After successful results, the foam was replaced by a lightweight carbon fibre mat to reduce the battery’s overall weight.

“Changing from stiff nickel foam to flexible carbon fibre mat makes the layer mimic the way small intestine works even further,” said study co-author Dr Yingjun Liu.

This functional layer, like the intestinal villi it resembles, has a very high surface area. The material has a very strong chemical bond with the poly-sulphides, allowing the active material to be used for longer, greatly increasing the lifespan of the battery.

“This is the first time a chemically functional layer with a well-organised nano-architecture has been proposed to trap and reuse the dissolved active materials during battery charging and discharging,” said the study’s lead author Teng Zhao, a PhD student from the Department of Materials Science & Metallurgy. “By taking our inspiration from the natural world, we were able to come up with a solution that we hope will accelerate the development of next-generation batteries.”

For the time being, the device is a proof of principle, so commercially-available lithium-sulphur batteries are still some years away. Additionally, while the number of times the battery can be charged and discharged has been improved, it is still not able to go through as many charge cycles as a lithium-ion battery. However, since a lithium-sulphur battery does not need to be charged as often as a lithium-ion battery, it may be the case that the increase in energy density cancels out the lower total number of charge-discharge cycles.

“This is a way of getting around one of those awkward little problems that affects all of us,” said Coxon. “We’re all tied in to our electronic devices – ultimately, we’re just trying to make those devices work better, hopefully making our lives a little bit nicer.”

Harvard University researchers have made the first entirely 3D-printed organ-on-a-chip with integrated sensing. Built by a fully automated, digital manufacturing procedure, the 3D-printed heart-on-a-chip can be quickly fabricated in customized form factors allowing researchers to easily collect reliable data for short-term and long-term studies.

This new approach to manufacturing may one day allow researchers to rapidly design organs-on-chips, also known as microphysiological systems, that match the properties of a specific disease or even an individual patient’s cells.

The research is published in Nature Materials.

“This new programmable approach to building organs-on-chips not only allows us to easily change and customize the design of the system by integrating sensing but also drastically simplifies data acquisition,” said Johan Ulrik Lind, first author of the paper and postdoctoral fellow at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). Lind is also a researcher at the Wyss Institute for Biologically Inspired Engineering at Harvard University.

“Our microfabrication approach opens new avenues for in vitro tissue engineering, toxicology and drug screening research,” said Kit Parker, Tarr Family Professor of Bioengineering and Applied Physics at SEAS, who coauthored the study. Parker is also a Core Faculty Member of the Wyss Institute.

Organs-on-chips mimic the structure and function of native tissue and have emerged as a promising alternative to traditional animal testing. Harvard researchers have developed microphysiological systems that mimic the microarchitecture and functions of lungs, hearts, tongues and intestines.

However, the fabrication and data collection process for organs-on-chips is expensive and laborious. Currently, these devices are built in clean rooms using a complex, multi-step lithographic process and collecting data requires microscopy or high-speed cameras.

“Our approach was to address these two challenges simultaneously via digital manufacturing,” said Travis Busbee, coauthor of the paper and graduate student in the Lewis Lab. “By developing new printable inks for multi-material 3D printing, we were able to automate the fabrication process while increasing the complexity of the devices.”

The researchers developed six different inks that integrated soft strain sensors within the micro-architecture of the tissue. In a single, continuous procedure, the team 3D printed those materials into a cardiac microphysiological device — a heart on a chip — with integrated sensors.

“We are pushing the boundaries of three-dimensional printing by developing and integrating multiple functional materials within printed devices,” said Jennifer Lewis, Hansjorg Wyss Professor of Biologically Inspired Engineering, and coauthor of the study. “This study is a powerful demonstration of how our platform can be used to create fully functional, instrumented chips for drug screening and disease modeling.”

Lewis is also a Core Faculty Member of the Wyss Institute.

The chip contains multiple wells, each with separate tissues and integrated sensors, allowing researchers to study many engineered cardiac tissues at once. To demonstrate the efficacy of the device, the team performed drug studies and longer-term studies of gradual changes in the contractile stress of engineered cardiac tissues, which can occur over the course of several weeks.

“Researchers are often left working in the dark when it comes to gradual changes that occur during cardiac tissue development and maturation because there has been a lack of easy, non-invasive ways to measure the tissue functional performance,” said Lind. “These integrated sensors allow researchers to continuously collect data while tissues mature and improve their contractility. Similarly, they will enable studies of gradual effects of chronic exposure to toxins.”

“Translating microphysiological devices into truly valuable platforms for studying human health and disease requires that we address both data acquisition and manufacturing of our devices,” said Parker. “This work offers new potential solutions to both of these central challenges.”

Researchers at Tokyo Institute of Technology in collaboration with the University of Cambridge have studied the interaction between microwave fields and electronic defect states inside the oxide layer of field-effect transistors at cryogenic temperatures. It has been found that the physics of such defect states are consistent with driven two-level systems possessing long coherence times, and that their induced dynamics can be coherently and independently controlled.

Due to the nature of this work, it is hoped that such results will contribute to the field of correlated electronic glassy dynamics in condensed matter physics; give a better understanding of charge noise effects in mesoscopic devices; and enable new studies for developing novel technologies in the important field of semiconductor-based quantum information processing.

(a) Schematic representation of the FET device used in this work. (b) Schematic diagram of the interaction between the trapped electron and the percolation pathways mediated by the MW field (top). Multilevel RTN events recorded in the FET current measured at 80 K (bottom). (c) Wideband CW microwave spectroscopy of the FET channel current performed at 4.2 K. Each narrow spike is a separate resonance that is resolved into a Fano or Lorentzian shape at higher resolution (inset). (d) Density of states (red), amplitude change (blue) and coherence times (inset) histograms. Credit: Nature Materials

(a) Schematic representation of the FET device used in this work. (b) Schematic diagram of the interaction between the trapped electron and the percolation pathways mediated by the MW field (top). Multilevel RTN events recorded in the FET current measured at 80 K (bottom). (c) Wideband CW microwave spectroscopy of the FET channel current performed at 4.2 K. Each narrow spike is a separate resonance that is resolved into a Fano or Lorentzian shape at higher resolution (inset). (d) Density of states (red), amplitude change (blue) and coherence times (inset) histograms. Credit: Nature Materials

Defect states acting as electron traps in oxide-semiconductor interfaces usually are sources of noise and tend to reduce the performance of nanoscale devices. Such defect states can modify the electrostatic environment experienced by conducting electrons, forcing them to percolate through nanowire-like pathways at low enough temperatures. This effectively allows a detection mechanism of the occupation of such trap sites by the current measured in the conduction channel. Such effect is normally observed as random telegraph noise (RTN), which corresponds to the incoherent emission and capture of electrons in the trap states, mediated by the thermal background.

Motivated by the big changes in the conductivity caused by RTN in field-effect transistors (FET), scientists at the Quantum Nanoelectronics Research Center, Institute of Innovative Research (Tokyo Tech), the Center for Advanced Photonics and Electronics (University of Cambridge), and Cavendish Laboratory (University of Cambridge) investigated possible mechanisms in which the occupation of defects states could be both observed and dynamically mediated by means of coherent microwave fields. Working at cryogenic temperatures, it was found that the dynamics of such trap states are consistent with two-level systems (TLS), in which the energy levels are discrete and only the two lowest are accessible within the energy of the excitation signal. A TLS can represent the basis for a quantum bit implementation.

From the microwave spectroscopic signature of the response of the FET used in this work, displaying a great number of high-quality factor resonances (Q > 10000), the extracted coherence times observed in this study are considerably longer, by almost three orders of magnitude, than other defect-based implementations of TLS. Performing single-pulse experiments gives the possibility to study the dynamics of the trapped electrons, which have been found not to depend on the chemistry of the dielectric used. And using a standard Ramsey protocol, coherent control was achieved. Furthermore, employing an optical master equation that captures the dynamics of the trapped electrons and a physical model based on linear response theory, it was possible to reproduce the experimental behavior observed in the experiments.

Furthermore, it was found that the defect states are relatively well protected against phonons, explaining the long decoherence times measured, and that the main source of back-action could be related to long-range Coulombic interactions with other charges. Finally, since each resonance can be addressed independently in frequency space, the wide distribution of long coherence times observed, and the quasi-uniform density of states measured, it is hoped that this work could motivate the possibility to use such systems as quantum memories or quantum bits in future quantum information processing implementations.

STMicroelectronics (NYSE: STM) today announced that its LSM6DSM 6-axis Inertial Measurement Unit (IMU) has earned certification for use in next-generation mobile devices running Google Daydream, a high-performance virtual-reality platform, and Tango, a platform that maps 3D space and enables it to be overlaid with virtual objects.

Announced at the Google I/O Developer Conference 2016, Daydream is being built into the newest generation of smartphones and other mobile devices and will operate along with a controller and a viewer to provide an amazing immersive virtual reality experience for exploring new worlds, enjoying entertainment with your own personal cinema and gaming.

Well suited to Daydream, Tango, and other mobile applications, ST’s 6-axis IMU, which integrates a 3-axis gyroscope and a 3-axis accelerometer, enables “always-on” sensing that maximizes battery life to stay on. The IMU’s efficient power-management techniques include an enhanced gyroscope design, energy-efficient data batching, and ST’s ultra-low-power process technology.

“Certification of ST’s 6-axis motion-sensing device for operation with Daydream and Tango for amazing virtual- and augmented-reality experiences demonstrates our abilities to design and deliver an exceptionally accurate and power-efficient IMU,” said Aymeric Gisselbrecht, Vice President Global Key Accounts Sales, STMicroelectronics. “Our long-term developments in sensing and actuation, along with our work with Google, are contributing to making mobile applications incredibly immersive and even more fun.”

In 2015, the Company’s net revenues were $6.90 billion, serving more than 100,000 customers worldwide.

A new type of atomic force microscope (AFM) uses nanowires as tiny sensors. Unlike standard AFM, the device with a nanowire sensor enables measurements of both the size and direction of forces. Physicists at the University of Basel and at the EPF Lausanne have described these results in the recent issue of Nature Nanotechnology.

A nanowire sensor measures size and direction of forces. Credit: University of Basel, Department of Physics

A nanowire sensor measures size and direction of forces. Credit: University of Basel, Department of Physics

Nanowires are extremely tiny filamentary crystals which are built-up molecule by molecule from various materials and which are now being very actively studied by scientists all around the world because of their exceptional properties.

The wires normally have a diameter of 100 nanometers and therefore possess only about one thousandth of a hair thickness. Because of this tiny dimension, they have a very large surface in comparison to their volume. This fact, their small mass and flawless crystal lattice make them very attractive in a variety of nanometer-scale sensing applications, including as sensors of biological and chemical samples, and as pressure or charge sensors.

Measurement of direction and size

The team of Argovia Professor Martino Poggio from the Swiss Nanoscience Institute (SNI) and the Department of Physics at the University of Basel has now demonstrated that nanowires can also be used as force sensors in atomic force microscopes. Based on their special mechanical properties, nanowires vibrate along two perpendicular axes at nearly the same frequency. When they are integrated into an AFM, the researchers can measure changes in the perpendicular vibrations caused by different forces. Essentially, they use the nanowires like tiny mechanical compasses that point out both the direction and size of the surrounding forces.

Image of the two-dimensional force field

The scientists from Basel describe how they imaged a patterned sample surface using a nanowire sensor. Together with colleagues from the EPF Lausanne, who grew the nanowires, they mapped the two-dimensional force field above the sample surface using their nanowire “compass”. As a proof-of-principle, they also mapped out test force fields produced by tiny electrodes.

The most challenging technical aspect of the experiments was the realization of an apparatus that could simultaneously scan a nanowire above a surface and monitor its vibration along two perpendicular directions. With their study, the scientists have demonstrated a new type of AFM that could extend the technique’s numerous applications even further.

AFM – today widely used

The development of AFM 30 years ago was honored with the conferment of the Kavli-Prize beginning of September this year. Professor Christoph Gerber of the SNI and Department of Physics at the University of Basel is one of the awardees, who has substantially contributed to the wide use of AFM in different fields, including solid-state physics, materials science, biology, and medicine.

The various different types of AFM are most often carried out using cantilevers made from crystalline Si as the mechanical sensor. “Moving to much smaller nanowire sensors may now allow for even further improvements on an already amazingly successful technique”, Martino Poggio comments his approach.