Originally posted by bpletcj
I couldn't get the link to work.
How and when did they invent it?
What was its original purpose?
"Microwires: Replacement For The CD-ROM?
A ballpoint that detects forgery of a signature and a substitute in miniature for the CD-ROM are some of the applications that can be carried out
Related News Stories
Scientists Help Police Bust Forgers (August 16, 2004) -- Forging wills and bank cheques could now be near impossible thanks to a team of physicists in
Rome (Italy). Writing in the latest issue of the Institute of Physics journal, Journal of Optics A, the ... > full story
Researchers Manipulate Tiny, Floating Droplets On A Chip (December 10, 2003) -- In an innovative study, researchers at North Carolina State University
have designed a way to control the movement of microscopic droplets of liquid freely floating across centimeter-sized chips ... > full story
Matter Waves On A Microchip: Munich Max-Planck Researchers Reached "Quantum Leap" To Miniaturize Atom Lasers (October 11, 2001) -- A few years ago,
the first atom lasers were built, devices that produce a beam of atoms with many of the properties of a laser beam. Now physicists at the Max Planck
Institute for Quantum Optics and ... > full story
Lawrence Livermore National Laboratory Develops Powerful New Rechargeable Battery (February 21, 2002) -- Researchers at Lawrence Livermore National
Laboratory have developed and demonstrated a laboratory prototype miniature thin-film fuel cell power source, which provides portable electrical power
for a ... > full story
> more related stories
Matter & Energy
Computers & Math
Three or five times thinner than a human hair, these fine threads were invented in the old Soviet Union for military purposes but, the broader
scientific community has been studying them for some time now for other applications – including at the University of the Basque Country (EHU).
Body and coating
Microwires have a metal body and a glass coating. The size of the metal body is usually about 1-20 μm radius and the glass coating of between 5
and 20 μm thickness Being so fine, the microthreads are totally flexible.
The main body of the microwire made of a ferromagnetic alloy, the composition of which varies depending on the metals used in the alloy and on the
final dimensions of the thread. As a result, by balancing these two factors, the range of microwires that can be obtained is very wide. But there is
one quality that they all have: they all have magnetic properties. It is precisely these magnetic properties and their diminutive size that make them
10 Megabits in 10 cm long
Amongst all the possible applications, the research team at the EHU has launched a similar project for using microwires as a system for storing
information. The microwires become diminutive substitutes for the CD-ROM, given that information can be stored magnetically on them, as with CDs.
To do this, researchers use a magnetic properties present in certain microwires: the magnetic bistability associated with a circular, "bamboo"-type
structure of domains. This structure presents positive and negative magnetising orientations at the surface of the microwire when this is subjected to
a magnetic field, i.e. the microwire becomes magnetised. As a result, the two orientations of the magnetisation at the surface can be interpreted as
the 1 and the 0 of a digital system (respectively positive and negative).
Taking this property into account, in order to create the replacement for the CD-ROM, the microwire has to be divided up along its length. Of course,
the thread cannot be sectioned – the divisions are carried out internally by means of a process of anisotrophy.
The researchers calculate that a 10 cm long microwire can carry out 10 million divisions or cells and in each one of these a bit can be stored. In
order to store the bit, each one of these cells is magnetised in one orientation or the other.
Once the information is recorded, a system for retrieving and reading it has to be devised. But the reading is not immediate. The initial response of
the reading is an electrical signal which has to be amplified and processed in an appropriate manner in order to access the real information.
These are the targets of this project – but, of course, it is no easy task. The greatest difficulty it seems will be with the reading of
information; i.e. the achievement of an electrical signal sufficiently suitable to be converted subsequently into a digital one."