How to Create the Tiniest MicroChip yet

he tiniest microchips yet can be made from graphene and other 2D-materials, using a form of ‘nano-origami’, physicists at the University of Sussex have found. This is the first time any researchers have done this, and it is covered in a paper published in the ACS Nano journal.

By creating kinks in the structure of graphene, researchers at the University of Sussex have made the nanomaterial behave like a transistor, and have shown that when a strip of graphene is crinkled in this way, it can behave like a microchip, which is around 100 times smaller than conventional microchips.

The base of the 2D-material with the white lines showing the structural kinks which modify the electrical properties mechanically.

We’re mechanically creating kinks in a layer of graphene. It’s a bit like nano-origami,”said Prof Alan Dalton in the School of Mathematical and Physical Sciences at the University of Sussex.

Using these nanomaterials will make our computer chips smaller and faster. It is absolutely critical that this happens as computer manufacturers are now at the limit of what they can do with traditional semiconducting technology. Ultimately, this will make our computers and phones thousands of times faster in the future.

“This kind of technology – “straintronics” using nanomaterials as opposed to electronics – allows space for more chips inside any device. Everything we want to do with computers – to speed them up – can be done by crinkling graphene like this.

Dr Manoj Tripathi, Research Fellow in Nano-structured Materials at the University of Sussex and lead author on the paper, explained: “Instead of having to add foreign materials into a device, we’ve shown we can create structures from graphene and other 2D materials simply by adding deliberate kinks into the structure. By making this sort of corrugation we can create a smart electronic component, like a transistor, or a logic gate.

Source: http://www.sussex.ac.uk/

World’s Smallest Atom-Memory Unit Created

Faster, smaller, smarter and more energy-efficient chips for everything from consumer electronics to big data to brain-inspired computing could soon be on the way after engineers at The University of Texas at Austin created the smallest memory device yet. And in the process, they figured out the physics dynamic that unlocks dense memory storage capabilities for these tiny devices.

The research published recently in Nature Nanotechnology builds on a discovery from two years ago, when the researchers created what was then the thinnest memory storage device. In this new work, the researchers reduced the size even further, shrinking the cross section area down to just a single square nanometer. Getting a handle on the physics that pack dense memory storage capability into these devices enabled the ability to make them much smaller. Defects, or holes in the material, provide the key to unlocking the high-density memory storage capability.

When a single additional metal atom goes into that nanoscale hole and fills it, it confers some of its conductivity into the material, and this leads to a change or memory effect,” said Deji Akinwande, professor in the Department of Electrical and Computer Engineering.

Though they used molybdenum disulfide – also known as MoS2 – as the primary nanomaterial in their study, the researchers think the discovery could apply to hundreds of related atomically thin materials.

The race to make smaller chips and components is all about power and convenience. With smaller processors, you can make more compact computers and phones. But shrinking down chips also decreases their energy demands and increases capacity, which means faster, smarter devices that take less power to operate.

The results obtained in this work pave the way for developing future generation applications that are of interest to the Department of Defense, such as ultra-dense storage, neuromorphic computing systems, radio-frequency communication systems and more,” said Pani Varanasi, program manager for the U.S. Army Research Office, which funded the research.

The original device – dubbed “atomristor” by the research team – was at the time the thinnest memory storage device ever recorded, with a single atomic layer of thickness. But shrinking a memory device is not just about making it thinner but also building it with a smaller cross-sectional area. “The scientific holy grail for scaling is going down to a level where a single atom controls the memory function, and this is what we accomplished in the new study,” Akinwande said.

Source: https://news.utexas.edu/

Augmented Reality A Hundred Times Less Expensive

Zombies or enemies flashing right before your eyes and the dizzying feeling of standing on the edge of a cliff using virtual reality and augmented reality (AR and VR) are no longer exclusive to the games or media industries. These technologies allow us to conduct virtual conferences, share presentations and videos, and communicate in real time in virtual space. But because of the high cost and bulkiness of VR and AR devices, the virtual world is not currently within easy reach.

Recently, a South Korean research team developed moldable nanomaterials and a printing technology using , allowing the commercialization of inexpensive and thin VR and AR devices.

Professor Junsuk Rho of the departments of mechanical engineering and chemical engineering and doctoral student in mechanical engineering Gwanho Yoon at POSTECH with Professor Heon Lee and researcher Kwan Kim of the department of material science at Korea University have jointly developed a new nanomaterial and large-scale nanoprinting technology for commercialization of metamaterials. The research findings, which solve the issue of device size and high production that were problematic in previous research, were recently published in Nature Communications.

Metamaterials are substances made from artificial atoms that do not exist in nature but freely control the properties of light. An invisible cloak that makes an illusion of disappearance by adjusting the refraction or diffraction of light, or metaholograms that can produce different hologram images depending on the direction of light’s entrance, uses this metamaterial. Using this principle, the ultrathin metalens technology, which can replace the conventional optical system with extreme thinness, was recently selected as one of the top 10 emerging technologies to change the world at the World Economic Forum last year.

In order to make metamaterials, artificial atoms smaller than the wavelengths of light must be meticulously constructed and arranged. Until now, metamaterials have been produced through a method called electron beam lithography (EBL). However, EBL has hindered the commercialization or production of sizable metamaterials due to its slow process speed and high cost of production. To overcome these limitations, the joint research team developed a new nanomaterial based on nanoparticle composite that can be molded freely while having optical characteristics suitable for fabricating metamaterials. The team also succeeded in developing a one-step printing technique that can shape the materials in a single-step process.

Source: http://postech.ac.kr/

Smart Materials Built With The Power Of Sound

Researchers have used sound waves to precisely manipulate atoms and molecules, accelerating the sustainable production of breakthrough smart materials.  Metal Organic Frameworks, or MOFs, are incredibly versatile and super porous nanomaterials that can be used to store, separate, release or protect almost anythingPredicted to be the defining material of the 21st century, MOFs are ideal for sensing and trapping substances at minute concentrations, to purify water or air, and can also hold large amounts of energy, for making better batteries and energy storage devices. Scientists have designed more than 88,000 precisely-customised MOFs – with applications ranging from agriculture to pharmaceuticals – but the traditional process for creating them is environmentally unsustainable and can take several hours or even days

Now researchers from RMIT in Australia have demonstrated a clean, green technique that can produce a customised MOF in minutes. Dr Heba Ahmed, lead author of the study published in Nature Communications, said the efficient and scaleable method harnessed the precision power of high-frequency sound waves.

Dr Heba Ahmed holding a MOF created with high-frequency sound waves

MOFs have boundless potential, but we need cleaner and faster synthesis techniques to take full advantage of all their possible benefits,” Ahmed, a postdoctoral researcher in RMIT’s Micro/Nanophysics Research Laboratory, said. “Our acoustically-driven approach avoids the environmental harms of traditional methods and produces ready-to-use MOFs quickly and sustainably. “The technique not only eliminates one of the most time-consuming steps in making MOFs, it leaves no trace and can be easily scaled up for efficient mass production.

Metal-organic frameworks are crystalline powders full of tiny, molecular-sized holes. They have a unique structuremetals joined to each other by organic linkers – and are so porous that if you took a gram of a MOF and spread out its internal surface area, you would cover an area larger than a football pitch. Some have predicted MOFs could be as important to the 21st  century as plastics were to the 20th.

During the standard production process, solvents and other contaminants become trapped in the MOF’s holes. To flush them out, scientists use a combination of vacuum and high temperatures or harmful chemical solvents in a process called “activation”. In their novel technique, RMIT researchers used a microchip to produce high-frequency sound waves. Co-author and acoustic expert Dr Amgad Rezk said these sound waves, which are not audible to humans, can be used for precision micro- and nano-manufacturing.

At the nano-scale, sound waves are powerful tools for the meticulous ordering and manoeuvring of atoms and molecules,” Rezk said.

Source: https://www.rmit.edu.au/