The storage capacity of hard disk drives could increase by a factor of five thanks to processes developed by chemists and engineers at The University of Texas at Austin.
The researchers’ technique, which relies on self-organizing substances known as block copolymers, was described this week in an article in Science. It’s also being given a real-world test run in collaboration with HGST, one of the world’s leading innovators in disk drives.
“In the last few decades there’s been a steady, exponential increase in the amount of information that can be stored on memory devices, but things have now reached a point where we’re running up against physical limits,” said C. Grant Willson, professor of chemistry and biochemistry in the College of Natural Sciences and the Rashid Engineering Regents Chair in the Cockrell School of Engineering.
With current production methods, zeroes and ones are written as magnetic dots on a continuous metal surface. The closer together the dots are, the more information can be stored in the same area. But that tactic has been pretty much maxed out. The dots have now gotten so close together that any further increase in proximity would cause them to be affected by the magnetic fields of their neighboring dots and become unstable.
“The industry is now at about a terabit of information per square inch,” said Willson, who co-authored the paper with chemical engineering professor Christopher Ellison and a team of graduate and undergraduate students. “If we moved the dots much closer together with the current method, they would begin to flip spontaneously now and then, and the archival properties of hard disk drives would be lost. Then you’re in a world of trouble. Can you imagine if one day your bank account info just changed spontaneously?”
There’s a quirk in the physics, however. If the dots are isolated from one another, with no magnetic material between them, they can be pushed closer together without destabilization.
This is where block copolymers come in. At room temperature, coated on a disk surface, they don’t look like much. But if they’re designed in the right way, and given the right prod, they’ll self-assemble into highly regular patterns of dots or lines. If the surface onto which they’re coated already has some guideposts etched into it, the dots or lines will form into precisely the patterns needed for a hard disk drive.
This process, which is called directed self-assembly (DSA), was pioneered by engineers at the University of Wisconsin and the Massachusetts Institute of Technology.
When Willson, Ellison and their students began working with directed self-assembly, the best anyone in the field had done was to get the dots small enough to double the storage density of disk drives. The challenge has been to shrink the dots further and to find processing methods that are compatible with high-throughput production.
The team has made great progress on a number of fronts. They’ve synthesized block copolymers that self-assemble into the smallest dots in the world. In some cases they form into the right, tight patterns in less than a minute, which is also a record.
“I am kind of amazed that our students have been able to do what they’ve done,” said Willson. “When we started, for instance, I was hoping that we could get the processing time under 48 hours. We’re now down to about 30 seconds. I’m not even sure how it is possible to do it that fast. It doesn’t seem reasonable, but once in a while you get lucky.”
Most significantly, the team has designed a special top coat that goes over the block copolymers while they are self-assembling.
“I’ve been fortunate enough to be involved in the experimental work of the top coat project from its inception all the way to our final results,” said Leon Dean, a senior chemical engineering major and one of the authors on the Science paper. “We’ve had to develop an innovative spin-on top coat for neutralizing the surface energy at the top interface of a block copolymer film.”
This top coat allows the polymers to achieve the right orientation relative to the plane of the surface simply by heating.
“The patterns of super small dots can now self-assemble in vertical or perpendicular patterns at smaller dimensions than ever before,” said Thomas Albrecht, manager of patterned media technology at HGST. “That makes them easier to etch into the surface of a master plate for nanoimprinting, which is exactly what we need to make patterned media for higher capacity disk drives.”
Willson, Ellison and their students are currently working with HGST to see whether these advances can be adapted to their products and integrated into a mainstream manufacturing process.
Other industry collaborators are Nissan Chemical Company, which partially funded the research, and Molecular Imprints, an Austin-based company co-founded by Willson that is a pioneer in nanoimprint lithography.
How many children do you have?
You are making the claim that evolution began in a warm pond, thus the burden is on your daughter monica
DNA Thumbs drive wrote:
There are no prebiotic molecules known, prebiotic molecules could only exist, if they were shown to have created life. Just as pre cancerous cells are shown to cause cancer.
No lifelessness of any type has been shown to create life, no matter how simple.
Quote:Researchers Discover an Important Pair of Prebiotic Molecules in Interstellar Space
Scientists using the Green Bank Telescope have discovered a pair of prebiotic molecules in interstellar space, suggesting that some basic chemicals needed for life may have formed on dusty ice grains floating between the stars.
The scientists used the National Science Foundation’s Green Bank Telescope (GBT) in West Virginia to study a giant cloud of gas some 25,000 light-years from Earth, near the center of our Milky Way Galaxy. The chemicals they found in that cloud include a molecule thought to be a precursor to a key component of DNA and another that may have a role in the formation of the amino acid alanine.
One of the newly-discovered molecules, called cyanomethanimine, is one step in the process that chemists believe produces adenine, one of the four nucleobases that form the “rungs” in the ladder-like structure of DNA. The other molecule, called ethanamine, is thought to play a role in forming alanine, one of the twenty amino acids in the genetic code.
“Finding these molecules in an interstellar gas cloud means that important building blocks for DNA and amino acids can ‘seed’ newly-formed planets with the chemical precursors for life,” said Anthony Remijan, of the National Radio Astronomy Observatory (NRAO).
In each case, the newly-discovered interstellar molecules are intermediate stages in multi-step chemical processes leading to the final biological molecule. Details of the processes remain unclear, but the discoveries give new insight on where these processes occur.
The possibility that terrestrial life may have extraterrestrial origins is given a boost: http://phys.org/news/2014-11-dna-survives-critical-entry-earth.html
Quote:DNA survives critical entry into Earth's atmosphere
Nov 26, 2014
The genetic material DNA can survive a flight through space and re-entry into the earth's atmosphere—and still pass on genetic information. A team of scientists from UZH obtained these astonishing results during an experiment on the TEXUS-49 research rocket mission.
Applied to the outer shell of the payload section of a rocket using pipettes, small, double-stranded DNA molecules flew into space from Earth and back again. After the launch, space flight, re-entry into Earth's atmosphere and landing, the so-called plasmid DNA molecules were still found on all the application points on the rocket from the TEXUS-49 mission. And this was not the only surprise: For the most part, the DNA salvaged was even still able to transfer genetic information to bacterial and connective tissue cells. "This study provides experimental evidence that the DNA's genetic information is essentially capable of surviving the extreme conditions of space and the re-entry into Earth's dense atmosphere," says study head Professor Oliver Ullrich from the University of Zurich's Institute of Anatomy.
No magical hand of a god required to explain earthly life forms, seems.
But the DNA could not survive entry into the Earths atmosphere if it was not already created. So what is your point? you seem to be making my points for me at this juncture and are unaware of this.
I love it when a plan comes together.
Dude I believe in evolution, of this there is ample evidence. However you have provided no evidence that a hard drive such as DNA can form in a pond, it's silly.
Please do not ask me to prove that DNA is a hard drive, as this is too easy.
DNA is the only molecule that replicates...........DNA has two main parts now, the hard drive proper, and the code on the drive.
How did life originate?
Living things (even ancient organisms like bacteria) are enormously complex. However, all this complexity did not leap fully-formed from the primordial soup. Instead life almost certainly originated in a series of small steps, each building upon the complexity that evolved previously:
Simple organic molecules were formed.
Simple organic molecules, similar to the nucleotide shown below, are the building blocks of life and must have been involved in its origin. Experiments suggest that organic molecules could have been synthesized in the atmosphere of early Earth and rained down into the oceans. RNA and DNA molecules — the genetic material for all life — are just long chains of simple nucleotides.
a nucleotide, composed of carbon, hydrogen, nitrogen, oxygen and phosphorus atoms
Replicating molecules evolved and began to undergo natural selection.
All living things reproduce, copying their genetic material and passing it on to their offspring. Thus, the ability to copy the molecules that encode genetic information is a key step in the origin of life — without it, life could not exist. This ability probably first evolved in the form of an RNA self-replicator — an RNA molecule that could copy itself.
Many biologists hypothesize that this step led to an "RNA world" in which RNA did many jobs, storing genetic information, copying itself, and performing basic metabolic functions. Today, these jobs are performed by many different sorts of molecules (DNA, RNA, and proteins, mostly), but in the RNA world, RNA did it all.
Self-replication opened the door for natural selection. Once a self-replicating molecule formed, some variants of these early replicators would have done a better job of copying themselves than others, producing more "offspring." These super-replicators would have become more common — that is, until one of them was accidentally built in a way that allowed it to be a super-super-replicator — and then, that variant would take over. Through this process of continuous natural selection, small changes in replicating molecules eventually accumulated until a stable, efficient replicating system evolved.
Replicating molecules became enclosed within a cell membrane.
The evolution of a membrane surrounding the genetic material provided two huge advantages: the products of the genetic material could be kept close by and the internal environment of this proto-cell could be different than the external environment. Cell membranes must have been so advantageous that these encased replicators quickly out-competed "naked" replicators. This breakthrough would have given rise to an organism much like a modern bacterium.
Cell membranes enclose the genetic material.
Some cells began to evolve modern metabolic processes and out-competed those with older forms of metabolism.
Up until this point, life had probably relied on RNA for most jobs (as described in Step 2 above). But everything changed when some cell or group of cells evolved to use different types of molecules for different functions: DNA (which is more stable than RNA) became the genetic material, proteins (which are often more efficient promoters of chemical reactions than RNA) became responsible for basic metabolic reactions in the cell, and RNA was demoted to the role of messenger, carrying information from the DNA to protein-building centers in the cell. Cells incorporating these innovations would have easily out-competed "old-fashioned" cells with RNA-based metabolisms, hailing the end of the RNA world.
DNA contains instructions. RNA copies DNA. Proteins are made from copies instructions.
As early as two billion years ago, some cells stopped going their separate ways after replicating and evolved specialized functions. They gave rise to Earth's first lineage of multicellular organisms, such as the 1.2 billion year old fossilized red algae in the photo below.
Bangiomorpha pubescens Bangiomorpha pubescens These fossils of Bangiomorpha pubescens are 1.2 billion years old. Toward the lower end of the fossil on the left there are cells differentiated for attaching to a substrate. If you look closely at the upper part of the fossil on the right, you can see longitudinal division that has divided disc-shaped cells into a number of radially arranged wedge-shaped cells, as we would see in a modern bangiophyte red alga.