Microwires: new CD-ROM?

2005/03/01 Andonegi Beristain, Garazi - Elhuyar Zientziaren Komunikazioa Iturria: Elhuyar aldizkaria

• Unibertsitateak
• Materialak

The pen, or replacement nimis of the CD-ROMs, able to detect if we are falsifying a signature, is one of the applications of microspeakers.

They are between 3 and 5 times smaller than a hair and were created in the Soviet Union for military uses. Currently, researchers are studying possible alternatives for other uses, including in the UPV.

Body and skin

Microhybrids have a metallic body and crystal skin. The metal body has a radius of 1-20 m and the glass top has a thickness of 5-20 m. Being thin, the microwire is totally flexible.

The metal body is composed of a ferromagnetic alloy that varies depending on the application. Taking into account the components of this alloy, and playing with the geometry that is given to the thread, different types of microspeakers can be made.

The variety is wide, but all have one characteristic: they have magnetic properties. These magnetic characteristics and their small sizes are so appreciated.

10 megabits at 10cm

Among all available applications, the UPV/EHU has launched a project to use microwires as information support. They want to use the microwires to store the bits, since, like on CD-ROMs, there is the possibility of storing the information magnetically.

For this purpose a special magnetic feature of several microns will be used: the magnetic bistability associated with circular fields in the form of bamboo. That is, if the microwire is distributed in circular fields like bamboo and a magnetic field is applied from the outside, these divisions are magnetized.

This magnetisation is circular and can go on the surface of the micro direction or counterclockwise. Therefore, depending on the direction, it can be interpreted as positive as 1 and negative as 0.

Therefore, the creation of alternatives to CD-ROMs involves the division of the microwire into circular areas. It is not possible to divide or interrupt the thread, but through a complex process it is possible to make divisions in the form of bamboo.

The researchers calculate that 10 million fragments or zones can be built in a 10 cm thread, each of which would store a bit. To save the bit, each of these fields will be displayed in one direction or another.

Once the information is recorded in the microhemia by magnetization, the researchers must guess how to read it. But reading is not immediate. In fact, in the first reading you will get an electric signal that will be extended and processed.

All this, however, will not be an easy task. The greatest difficulties are in reading, obtaining the right electrical signal before digitizing.

• Project Title Magnetohazard and magnetogranate process in designed materials.
• Objective To study in depth the mechanisms of magnetic bistability of microhysos and the influence of production parameters on amorphous microspeakers.
• Director Arcady P. Zhukov.
• Team J.M. Gonzalez, J.M. White, O. Chizhik, J.J. del Val, M.L. Dominguez, A. Fernandez, C. García.
• Departments Department of Materials Physics and Applied Physics Section 1.
• Faculty of Chemistry and University School of Industrial Technical Engineering.
• MEC funding (2004-2007).