Very Fast Magnetic Data Storage

For almost seventy years now, magnetic tapes and hard disks have been used for data storage in computers. In spite of many new technologies that have been developed in the meantime, the controlled magnetization of a data storage medium remains the first choice for archiving information because of its longevity and low price. As a means of realizing random access memories (RAMs), however, which are used as the main memory for processing data in computers, magnetic storage technologies were long considered inadequate. That is mainly due to its low writing speed and relatively high energy consumption.

In 1956, IBM introduced the first magnetic hard disc, the RAMAC. ETH researchers have now tested a novel magnetic writing technology that could soon be used in the main memories of modern computers

Pietro Gambardella, Professor at the Department of Materials of the Eidgenössische Technische Hochschule Zürich (ETHZ, Switzerland), and his colleagues, together with colleagues at the Physics Department and at the Paul Scherrer Institute (PSI), have now shown that using a novel technique, magnetic storage can still be achieved very fast and without wasting energy.

In 2011, Gambardella and his colleagues already demonstrated a technique that could do just that: An electric current passing through a specially coated semiconductor film inverted the magnetization in a tiny metal dot. This is made possible by a physical effect called spin-orbit-torque. In this effect, a current flowing in a conductor leads to an accumulation of electrons with opposite magnetic moment (spins) at the edges of the conductor. The electron spins, in turn, create a magnetic field that causes the atoms in a nearby magnetic material to change the orientation of their magnetic moments. In a new study the scientists have now investigated how this process works in detail and how fast it is.

The results were recently published in the scientific journal Nature Nanotechnology.


Robot Mother Builds Its Own Children

Researchers led by the University of Cambridge have built a mother robot that can independently build its own children and test which one does best; and then use the results to inform the design of the next generation, so that preferential traits are passed down from one generation to the next. Without any human intervention or computer simulation beyond the initial command to build a robot capable of movement, the mother created children constructed of between one and five plastic cubes with a small motor inside. In each of five separate experiments, the mother designed, built and tested generations of ten children, using the information gathered from one generation to inform the design of the next.

mother robot

Natural selection is basically reproduction, assessment, reproduction, assessment and so on,” said lead researcher Dr Fumiya Iida of Cambridge’s Department of Engineering, who worked in collaboration with researchers at ETH Zurich. “That’s essentially what this robot is doing – we can actually watch the improvement and diversification of the species.” For each robot child, there is a unique ‘genome’ made up of a combination of between one and five different genes, which contains all of the information about the child’s shape, construction and motor commands. As in nature, evolution in robots takes place through ‘mutation’, where components of one gene are modified or single genes are added or deleted, and ‘crossover’, where a new genome is formed by merging genes from two individuals.
The results, reported in the open access journal PLOS One, found that preferential traits were passed down through generations, so that the ‘fittest’ individuals in the last generation performed a set task twice as quickly as the fittest individuals in the first generation.


Nanorobots Swim Through Blood To Deliver Drugs

Someday, treating patients with nanorobots could become standard practice to deliver medicine specifically to parts of the body affected by disease. But merely injecting drug-loaded nanoparticles might not always be enough to get them where they need to go. Now scientists are reporting in the ACS journal Nano Letters the development of new nanoswimmers that can move easily through body fluids to their targets.
nanorobots to deliver drugsCLICK ON THE IMAGE TO ENJOY THE VIDEO

Tiny robots could have many benefits for patients. For example, they could be programmed to specifically wipe out cancer cells, which would lower the risk of complications, reduce the need for invasive surgery and lead to faster recoveries. It’s a burgeoning field of study with early-stage models currently in development in laboratories. But one of the challenges to making these robots work well is getting them to move through body fluids, which are like molasses to something as small as a nanorobot. Bradley J. Nelson, Salvador Pané, from ETH Zürich (Switzerland), Yizhar Or from Technion (Israel)  and colleagues wanted to address this problem. The researchers strung together three links in a chain about as long as a silk fiber is wide. One segment was a polymer, and two were magnetic, metallic nanowires. They put the tiny devices in a fluid even thicker than blood. And when they applied an oscillating magnetic field, the nanoswimmer moved in an S-like, undulatory motion at the speed of nearly one body length per second. The magnetic field also can direct the swimmers to reach targets.


Tiny Magnetic DNA Used As Invisible Label

The worldwide need for anti-counterfeiting labels for food is substantial. In a joint operation in December 2013 and January 2014, Interpol and Europol confiscated more than 1,200 tonnes of counterfeit or substandard food and almost 430,000 litres of counterfeit beverages. The illegal trade is run by organised criminal groups that generate millions in profits, say the authorities. The confiscated goods also included more than 131,000 litres of oil and vinegar. A forgery-proof label should not only be invisible but also safe, robust, cheap and easy to detect. To fulfil these criteria ETH researchers – Switzerland – used nanotechnology and nature’s information storehouse, DNA. A piece of artificial genetic material is the heart of the mini-label.
Just a few grams of the new substance are enough to tag the entire olive oil production of Italy. If counterfeiting were suspected, the particles added at the place of origin could be extracted from the oil and analysed, enabling a definitive identification of the producer.

Using magnetic DNA particles, olive oil can be tagged to prevent counterfeiting
The method is equivalent to a label that cannot be removed,” says Robert Grass, lecturer in the Department of Chemistry and Applied Biosciences at ETH Zurich.
However, DNA also has some disadvantages. If the material is used as an information carrier outside a living organism, it cannot repair itself and is susceptible to light, temperature fluctuations and chemicals. Thus, the researchers used a silica coating to protect the DNA, creating a kind of synthetic fossil. The casing represents a physical barrier that protects the DNA against chemical attacks and completely isolates it from the external environment – a situation that mimics that of natural fossils, write the researchers in their paper, which has been published in the journal ACS Nano.

Electric Car: The Battery Of The Future

More powerful batteries could help electric cars achieve a considerably larger range and thus a breakthrough on the market. Laboratory of Inorganic Chemistry at ETH Zurich and Empa -Switzerland – have now developed a nanomaterial which enables considerably more power to be stored in lithium ion batteries. They provide power not only for electric cars, but also for electric bicycles, smartphones and laptops; nowadays, rechargeable lithium ion batteries are the storage media of choice when it comes to supplying a large amount of energy in a small space and light weight.


Monodisperse tin nanodroplets in an electron microscopic

During the development of the nanomaterial, the issue of the ideal size for the nanocrystals arose, which also carries the challenge of producing uniform crystals. “The trick here was to separate the two basic steps in the formation of the crystals – the formation of as small as a crystal nucleus as possible on the one hand and its subsequent growth on the other,” explains Maksym Kovalenko, head of the research team at ETH Zurich. By influencing the time and temperature of the growth phase, the scientists were able to control the size of the crystals. “We are the first to produce such small tin crystals with such precision,” says the scientist.