As the transistor revolutionized the world of electronics, the idea of spintronics will pave the way for the creation of state-of-the-art devices that are not limited by the factors of today's semiconductors. There will be a free lecture led by the experts that have made UB an international leader in the area.
Igor Zutic, Ph.D., an assistant professor of physics at UB, will be speaking about the potential future of electronics on Friday at 7:30 p.m. in 112 Norton Hall. The lecture entitled "Putting Spin into Electronics: Vision for the Future" is open to the public and is part of a symposium honoring the work of Bruce McCombe, a Distinguished Professor of Physics and Dean of the College of Arts and Sciences at UB.
The lecture will showcase the fundamental principles of real world applications of this subfield of physics. Zutic said he will demonstrate the principles behind magnetic levitation, which could pave the way for levitation modes of transportation.
The lecture will also feature bacteria growing magnets inside themselves.
"If you're a small organism and you're in a muddy pond how do you know what's up and what's down," Zutic said. "Using earth's magnetic field one can figure out direction and get quickly to the source of food."
Magnetism is special, Zutic said, if you have a magnet on a fridge the magnet requires no external power source to stay on the fridge. Another useful property of magnets is their ability to transfer their magnetic properties to non-magnetic materials temporarily.
"These two factors make it really useful in studying the potential for storing and processing information because you don't need energy," Zutic said.
Current methods involving semiconductors require electricity to maintain the current state. Semiconductors maintain their combinations and manipulations of zeros and ones by using charges. The problem with current semiconductors is that they are reaching their physical limitation, Zutic explained.
"Moore's law states that the number of transistors on a chip will double every 18 months to two years," Zutic said. "However, the more transistors you add to a chip, the more energy that is required to power that chip and the more heat that will be generated. Transistors can only get so small, eventually the heat will be too much and physically you won't be able to do much else."
The answer to these limitations of today is spintronics, a term combining spin and electronics. Spin refers to the properties of magnetism much like charge is a property of electrons; while electrons can have a positive or negative charge, magnetic particles can have a "spin up" or a "spin down" property.
Current semiconductors are non-magnetic; however, recent research has integrated adding magnetic impurities into the semiconductor during the creation phase. This creates a semiconductor that cannot only manipulate charge but also can preserve magnetism without a power source at the same time.
It takes much less energy to change the spin property of magnets than it does to move electrons from left to right or on to off, Zutic said. He explained that if magnetic properties could be applied to semiconductors then the power usage would drop drastically causing heat problems to disappear. The goal is to fabricate materials to combine two materials into one.
Superconductors are materials that conduct electricity perfectly without any loss to heat or external factors. They also exhibit magnetic properties in that they "hate" magnets. If a magnet comes near a superconductor, it will automatically be repelled without any power source. This concept drives the idea of magnetic levitation, which could power trains, which is slowly moving towards practical application.
The potential is great, but there is a catch - superconductors only exhibit superconductor properties at lower temperatures.
In order to operate, superconductors need to be cooled. One way to do that is by using something such as liquid nitrogen, which is very cost-efficient, Zutic said. But commercialization is a long ways away.
"It's difficult to make an accurate assessment," Zutic said. "However, at minimum - ten years."
Photo: Courtesy of Laron Fomby
