Nanomagnetism for more powerful devices

29 de October de 2014

Nanomagnetic technology can be used to develop devices with more durable batteries and increased storage memories.

Magnetricity can be used to produce more powerful and smaller cell phones and computers, as an alternative to the use of electricity. Devices developed with the use of nanomagnetism have greater potential for information storage and transportation. Researchers of the UFV Graduate Program in Applied Physics have demonstrated for the first time that monopoles can be created in nanostructured magnetic systems – the so called artificial spin ice. In these systems, positive and negative magnetic poles seem to separate. The movement of isolated magnetic charges can generate a current called magnetricity.

The physicist Clodoaldo Irineu Levartoski de Araújo, leader of this UFV research, states that the team works with magnetism in nanoscale, namely, in a very small dimension. That is why they talk about nanoscale devices. “When we decrease the size of things, we can control magnetic properties better” – he explains.

Nanoscale devices can be used to develop, for example, devices with more durable batteries and enlarged storage memories. The UFV researcher declares that nanomagnetism is a promising technology because it increases freedom and information density. It can also improve the speed of instruments and save energy, since these devices do not heat. The physicist also believes that this technology will be cheaper than those currently used, such as silicon and electrical charge, because few steps are necessary to obtain a nanometric device.

To obtain a nanomagnetic device, the researchers produce thousands of very small magnets, invisible to the naked eye, and arrange them in arrays on a certain surface. An emerging particle that behaves like a single-pole magnet comes from this controlled geometry. The researcher states that “by 2010, these emerging poles had never been experimentally observed. They were provided only in theory. The movement of isolated poles generating a magnetic current was first performed at UFV. “

The geometry used in this system is called Spin Ice due to its similarities with the configuration of water ice. Using a special microscope, researchers can visualize the spin ices and can control the current of magnetic monopoles. Professor Araújo explains that the UFV research group artificially creates magnetic monopoles and makes them move, thus generating magnetron current or magnetricity. He adds that it is possible to make islands that generate monopoles as desired: “you can manipulate and change the designs to achieve better results.”

The analysis and characterization of nanomagnetic devices are developed at the UFV, while the manufacturing of samples of nanostructures is conducted by the UFV team at the Centro Brasileiro de Pesquisas Físicas (CBPF) (Brazilian Center for Physics Research), located in Rio de Janeiro, since it has a nanolithography machine. Today, the CBPF and Universidade de Campinas (Unicamp) are the only Brazilian institutions that have this equipment. Professor Araújo declared that the UFV also intends to purchase a nanolithography machine. This will allow the UFV to manufacture its own samples and train researchers in the use of the equipment. Nowadays, Professor Araújo is one of the few Brazilian researchers able to operate it. He asserts: “we are interested in developing new technologies and training human resources.”

The physicist explains that nanostructures are necessary, since research has focused on technological application. The research is in its early stages, but has already proven that magnetic charge can be generated through nanostructures. The UFV researcher highlights: “Physics shows the feasibility of things and engineers adapt them to the market.” It is clear that this new technology can be applied in many ways, since nanometric devices can meet the need for increasingly powerful and smaller devices.