Microwires as mobile phone sensors

January 28, 2014

Microwires were created in the former Soviet Union for military purposes. They formed the basis of the camouflage of a model of spy plane used by the Soviet army, but for a long time the scientific community has been studying them for other purposes. A study by the UPV/EHU's Magnetism Group is making progress in furthering understanding of the surface magnetic behaviour of glass-coated microwires and has concluded that they are the major candidates for use as high sensitivity sensors, in mobile phones, for example.

Microwires have a metal core and a crystal skin, in other words, they have a glass coating. The core of the microwire consists of a ferromagnetic alloy, which varies according to the metals used in the alloy and the final geometry of the wire. "But there is a quality that they all share: they have magnetic properties. It is precisely their magnetic properties and small size that account for the fact that they are so prized," pointed out Alexander Chizhik, a member of the Magnetism group.

"One of the possibly best-known applications with respect to microwires is that they can be used as sensors in the electronic compasses of mobile phones," said Chizhik. "These are sensors that allow the position of the mobile phone owner to be determined in space just as if the device were a GPS." Like the sensors in mobile phones, various sensors developed in collaboration with the Japanese company Aichi are currently being used in the automotive industry or in traffic surveillance vehicles.

Magnetic structure

Right now, the mass production of these sensors is closely related to the ability to reproduce the properties of the wires and the homogeneities of these properties throughout the length of the microwire. So "the main task in our work is to choose the optimum parameters of the magnetic microwires in order to obtain a higher level of reproducibility," explained Chizhik.

That is why the aim of this research is part of the intense work that the Magnetism group has been carrying out over the last 25 years involving studies into the magnetic properties of new materials. In this context, "particular attention has been paid to the quest for new applications for these tiny wires," explained Alexander Chizhik. "Our study makes it possible to go further into the understanding of the surface magnetic behaviour of glass-coated microwires," he added.

Specifically, the UPV/EHU's Magnetism Group has concentrated on studying the magnetic structure of microwires. They are using a laser to do this. The light emitted from this device is reflected onto the microwire and gathers all the information about the microwire's magnetic, electrical, and atomic, etc. structure. "Let's say this microwire functions like a mirror," added the Magnetism Group researcher. That way "we have managed to study the magnetic structure of the microwires in depth and see that they display a unique structure of magnetic domains," as Alexander Chizhik pointed out. "This structure of magnetic domains provides microwaves with great sensitivity. It is a very important factor to take into consideration, because sensors have to have a degree of sensitivity that is higher than the rest in order to pick up low-intensity signals," he added.

He concluded by saying, "Thanks to this study, we have also verified that if we apply an electric current to microwires, the magnetic domain structure varies; so this is an important factor for these sensors to work well".
-end-


Elhuyar Fundazioa

Related Sensors Articles from Brightsurf:

OPD optical sensors that reproduce any color
POSTECH Professor Dae Sung Chung's team uses chemical doping to freely control the colors of organic photodiodes.

Airdropping sensors from moths
University of Washington researchers have created a sensor system that can ride aboard a small drone or an insect, such as a moth, until it gets to its destination.

How to bounce back from stretched out stretchable sensors
Elastic can stretch too far and that could be problematic in wearable sensors.

New mathematical tool can select the best sensors for the job
In the 2019 Boeing 737 Max crash, the recovered black box from the aftermath hinted that a failed pressure sensor may have caused the ill-fated aircraft to nose dive.

Lighting the way to porous electronics and sensors
Researchers from Osaka University have created porous titanium dioxide ceramic thin films, at high temperatures and room temperature.

Russian scientists to improve the battery for sensors
Researchers of Peter the Great St. Petersburg Polytechnic University (SPbPU) approached the creation of a solid-state thin-film battery for miniature devices and sensors.

Having an eye for colors: Printable light sensors
Cameras, light barriers, and movement sensors have one thing in common: they work with light sensors that are already found in many applications.

Improving adhesives for wearable sensors
By conveniently and painlessly collecting data, wearable sensors create many new possibilities for keeping tabs on the body.

Kirigami inspires new method for wearable sensors
As wearable sensors become more prevalent, the need for a material resistant to damage from the stress and strains of the human body's natural movement becomes ever more crucial.

Wearable sensors detect what's in your sweat
A team of scientists at the University of California, Berkeley, is developing wearable skin sensors that can detect what's in your sweat.

Read More: Sensors News and Sensors Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.