Spintronics

A team of scientists led by Associate Professor Yang Hyunsoo from the National University of Singapore’s (NUS) Faculty of Engineering has invented a novel ultra-thin multilayer film which could harness the properties of tiny magnetic whirls, known as skyrmions, as information carriers for storing and processing data (nanocomputer) on magnetic media. The nano-sized thin film, which was developed in collaboration with researchers from Brookhaven National Laboratory, Stony Brook University, and Louisiana State University, is a critical step towards the design of data storage devices that use less power and work faster than existing memory technologies.

The digital transformation has resulted in ever-increasing demands for better processing and storing of large amounts of data, as well as improvements in hard drive technology. Since their discovery in magnetic materials in 2009, skyrmions, which are tiny swirling magnetic textures only a few nanometres in size, have been extensively studied as possible information carriers in next-generation data storage and logic devices.

Skyrmions have been shown to exist in layered systems, with a heavy metal placed beneath a ferromagnetic material. Due to the interaction between the different materials, an interfacial symmetry breaking interaction, known as the Dzyaloshinskii-Moriya interaction (DMI), is formed, and this helps to stabilise a skyrmion. However, without an out-of-plane magnetic field present, the stability of the skyrmion is compromised. In addition, due to its tiny size, it is difficult to image the nano-sized materials. The NUS team found that a large DMI could be maintained in multilayer films composed of cobalt and palladium, and this is large enough to stabilise skyrmion spin textures.

skyrmionsThis experiment not only demonstrates the usefulness of L-TEM in studying these systems, but also opens up a completely new material in which skyrmions can be created. Without the need for a biasing field, the design and implementation of skyrmion based devices are significantly simplified. The small size of the skyrmions, combined with the incredible stability generated here, could be potentially useful for the design of next-generation spintronic devices that are energy efficient and can outperform current memory technologies,” explains Professor Yang .

The invention was reported in the journal Nature Communications.

Source: http://news.nus.edu.sg

DNA DataStorage, New Frontier For Nanotechnology

Nanotechnology holds a lot of promise to almost every aspect of our lives from consumer electronics to ending life-threatening illnesses. However, the greatest challenge nanotechnology is facing is the limitation of how much smaller they can shrink the physical size of semiconductors. However, a group of scientists are taking that challenge and if they are successful, we may be well on our way to a future much wilder than science fiction – molecular electronics.

dna

Molecular electronics works at the most minute scale using single molecules including its sub properties and characteristics. The concept of molecular electronics was first originated in 1997 by Mark Reed and his colleagues.

This is what a team of Russian and Israeli scientists are trying to explore as the demand for smaller electronic devices proliferate. Their study proposes to “metallizeDNA using nanoparticles of silver.

First of all, the DNA can hold a great amount of information despite its small size. What’s more intriguing is that the ability of DNA is not limited to storing only genetic information. The study has revealed that the DNA has more uncanny and unique features.

The first feature they discovered was that the DNA has superconducting abilities when placed between two superconductors. The second feature was that they can effect charge transport, which happen when you introduce metal atoms along the strand. Moreover, the scientists also discovered that the conductivity of the DNA molecules depend on the type of substrate they are placed on.

Although the scientists were able to ‘metallize‘ atoms, the distribution was not even along the entire length of the strands, which means not all of it becomes ‘metal.’ However, they found out that these DNA molecules can interact with silver nanoparticles resulting in an even metal DNA strand.

If further experimentation and testing become successful, such nanowire would be 1.1 nanometers high and 400 nanometers long.

The study is published in Advanced Materials.

Source: http://www.universityherald.com/

Towards The Bionic Brain

RMIT University (Australia) researchers have brought ultra-fast, nano-scale data storage within striking reach, using technology that mimics the human brain. The researchers have built a novel nano-structure that offers a new platform for the development of highly stable and reliable nanoscale memory devices, useful for nanocomputers. Project leader Dr Sharath Sriram, co-leader of the RMIT Functional Materials and Microsystems Research Group, said the nanometer-thin stacked structure was created using thin film, a functional oxide material more than 10,000 times thinner than a human hair.

Brain Cells
The thin film is specifically designed to have defects in its chemistry to demonstrate a ‘memristive‘ effect – where the memory element’s behaviour is dependent on its past experiences,” Dr Sriram said. “With flash memory rapidly approaching fundamental scaling limits, we need novel materials and architectures for creating the next generation of non-volatile memory. “The structure we developed could be used for a range of electronic applications – from ultrafast memory devices that can be shrunk down to a few nanometers, to computer logic architectures that replicate the versatility and response time of a biological neural network. “While more investigation needs to be done, our work advances the search for next generation memory technology can replicate the complex functions of human neural system – bringing us one step closer to the bionic brain.

The pioneering work will be published in the journal Advanced Functional Materials (11 November).

Source: http://www.rmit.edu.au

Ultra-Fast Computer Memory For Smartphones and Tablets

By using electric voltage instead of a flowing electric current, researchers from UCLA‘s Henry Samueli School of Engineering and Applied Science have made major improvements to an ultra-fast, high-capacity class of computer memory known as magnetoresistive random access memory, or MRAM.. The UCLA team’s improved memory, which they call MeRAM for magnetoelectric random access memory, has great potential to be used in future memory chips for almost all electronic applications, including smart-phones, tablets, computers and microprocessors, as well as for data storage, like the solid-state disks used in computers and large data centers.
The research team was led by principal investigator Kang L. Wang, UCLA‘s Raytheon Professor of Electrical Engineering, and included lead author Juan G. Alzate, an electrical engineering graduate student, and Pedram Khalili, a research associate in electrical engineering and project manager for the UCLA–DARPA research programs in non-volatile logic.


The ability to switch nanoscale magnets using voltages is an exciting and fast-growing area of research in magnetism,” Khalili said. “This work presents new insights into questions such as how to control the switching direction using voltage pulses, how to ensure that devices will work without needing external magnetic fields, and how to integrate them into high-density memory arrays“.

Source: http://newsroom.ucla.edu/

10 Terabits Data Storage On A Fingernail

Imagine being able to store thousands of songs and high-resolution images on data devices no bigger than a fingernail. Researchers from A*STAR’s Institute of Materials Research and Engineering (IMRE) and the National University of Singapore (NUS) have discovered that an ultra-smooth surface is the key factor for “self-assembly” – a cheap, high-volume, high-density patterning technique.

This allows manufacturers to use the method on a variety of different surfaces.The discovery paves the way for the development of next generation data storage devices, with capacities of up to 10 Terabits/in2 which could lead to significantly greater storage on much smaller data devices.

Source: http://www.a-star.edu.sg/

One-Inch Chip Storing Terabytes Of Data

A multi-institutional team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has provided the first atomic-scale insights into the ferroelectric properties of nanocrystals. This breakthrough is critical for the development of the next generation of data storage devices as  one-inch chips storing terabytes of data. Working with the world’s most powerful transmission electron microscope, the researchers mapped the ferroelectric structural distortions in nanocrystals of germanium telluride, a semiconductor, and barium titanate, an insulator.

 

Atomic-resolution images of germanium telluride nanoparticles from Berkeley Lab’s TEAM I electron microscope, and electron holographic images of barium titanate nanoparticles (below) from BNL yielded the first detailed experimental information on ferroelectric order at the nanoscale.

As we scale down our device technology from the microscale to the nanoscale, we need a better understanding of how critical material properties, such as ferroelectric behavior, are impacted,” says Paul Alivisatos, director of Berkeley Lab and one of the principal investigators in this research. “Our results provide a pathway to unraveling the fundamental physics of nanoscale ferroelectricity at the smallest possible size scales.
Let's remind similar researches by an IBM team, described in a Nanocomputer.com former article. 
http://www.nanocomputer.com/?p=1620, and by a french team from CNRS-Paris. http://www.nanocomputer.com/?p=2590

Source: http://newscenter.lbl.gov/feature-stories/2012/07/10/ferroelectricity-on-the-nanoscale/