A huge number of boffins has come up with a way to control and measure spin current in semiconductors using a method similar to electrical current.
Scientists at Hitachi Cambridge Laboratory of Hitachi Europe along with the University of Cambridge, University of Nottingham, the Institute of Physics of the Academy of Sciences and Charles University of the Czech Republic, and the Texas A&M University in the US, have developed the new technique using gallium-arsenide semiconductor material.
Electronic devices such as information processing, semiconductor, storage and power devices which have been the driving force in the rapid advancement of industry, social infrastructure, lifestyle and science in the 20th century, have previously been based on detecting the basic attribute of the “charge” of an electron.
However, according to Joerg Wunderlich, who heads up the team of researchers at Hitachi Cambridge Laboratory, this hasn’t moved on until now.
He told TechEye that the new science and technology field of spintronics is based on the other basic attribute of an electron. This is the elementary magnetic moment, which is otherwise known as the “spin.”. This is an area which has attracted high expectations as it is believed that this could push forward a new way for low-power consuming electronics, hybrid electric-magnetic systems and completely new technologies.
Joerg Wunderlich told us: “The research into the new spinning began in 2005, when scientists realised they were able to measure separately an up and down spin at an extremely low temperature of -269C using a gallium-arsenide semiconductor, a non-magnetic material.”
He added that in 2009, they were able to use the same gallium arsenide semiconductor at a temperature of -53C, by measuring the flow of spin polarised current over a distance of a few microns.
“In the current development, the up or down spin was controlled by a gate voltage, and the ON/OFF operation as a transistor verified,” he added.
“In this development, a circularly polarised light 4 was used to generate pure spin current in the semiconductor. However this is just the start. In the future when spin-injection technology for ferromagnetic material is developed, the all solid spintronics devices will be achieved.”
He added that further technology will also help researchers to use a solid device which can control and detect the polarisation of the light. This means that this can be used to open the way for even larger capacity information transmission systems.
Wunderlich said that the technology, which is still in its “early stages” will be used by Hitachi as well as other companies.