The movement of electrons might have a significantly greater influence on spintronic effects than it was previously assumed claims a new study. So far, calculation of these effects has been primarily taken into account during the spin of the electrons. This discovery has been made by an international team of researchers led by physicists from Martin Luther University Halle-Wittenberg (MLU). While doing so, the spin of the electrons was primarily taken into account. The study has been published in the journal "Physical Review Research" and offers a new approach in the development of spintronic components.
Many technical devices nowadays are based on conventional semiconductor electronics according to which, charging currents are used to store and process information in these components. However, the major drawback of this conventional method is that a lot of energy is lost due to the heat generated by the current. In order to deal with this, spintronics uses a fundamental property of electrons known as intrinsic angular momentum that can be thought of as the rotational movement of an electron about its own axis, explains Dr. Annika Johansson, physicist from MLU. The spin is linked to a magnetic moment that could also be used to charge the electrons in a new generation of faster and more energy-efficient components. To achieve this, an efficient conversion between loads and spin currents is required. This conversion is made possible by the gemstone effect. According to the gemstone effect, by applying an electric field, the charging current is generated in an originally non-magnetic material. The charging current leads to alignment of the electrons spin and the material becomes magnetized. ”The effect primarily focus on how the electron spin contributes to magnetization, but electrons can also carry an orbital moment that also contributes to magnetization. “If the spin is the electron's rotation about its own axis, then the orbital moment is the movement around the atomic nucleus”, says Johansson. This is similar to the earth, which rotates both about its own axis and around the sun. Orbital moment thus, also creates a magnetic moment.
Researchers in their new study have used simulations to study the interface between two oxide materials commonly used in spintronics. Although both materials are insulators, there is a metal-electron gas at their interface, which is known for its efficient conversion of charge into spin. The team also considered orbital moment while calculating the gemstone effect and found that the orbital moment has more contribution to the gemstone effect than that of a spin. These findings could help increase the efficiency of spintronic components.
