Spintronic devices based on quantum materials operate at very low consumption

As artificial intelligence technologies such as Chat-GPT are used in various industries, the role of high-performance semiconductor devices for processing large amounts of information is becoming increasingly important. Among them, spin memory attracts attention as a next-generation electronic technology because it is suitable for processing large amounts of information with lower power than currently mass-produced silicon semiconductors.

The use of newly discovered quantum materials in spin memory is expected to significantly improve performance by improving signal ratio and reducing power, but to achieve this it is necessary to develop technologies to control the properties of quantum materials by electrical methods such as current and voltage.

Dr. Jun Woo Choi from the Korea Institute of Science and Technology (KIST) Spintrunk Research Center and Professor Se-Young Park from the Department of Physics at Soongsil University announced the results of a collaborative study showing than ultra-low-power memory can be made from quantum materials. The results are published in the journal Natural communications.

By applying a voltage to a quantum material spintronic device consisting of a two-dimensional material heterostructure, it is possible to read and write information at very low power by effectively controlling the electron spin information.

Two-dimensional materials, which are representative quantum materials, can be easily separated into planar layers of single atoms, unlike ordinary materials which have a three-dimensional structure and thus exhibit special quantum mechanical properties.

In this study, researchers developed for the first time a two-dimensional heterostructure device that combines quantum materials with two different properties for the first time. By applying a voltage as low as 5 V to a device made of a two-dimensional ferromagnetic material (Fe_3-xGet₂) and a two-dimensional ferroelectric material (In₂Se₃) stacked on top of each other, the magnetic field required to change the direction of rotation of the ferromagnet, i.e. coercivity, can be reduced by more than 70%.

The researchers also discovered that structural changes in the two-dimensional ferroelectric that occur when a voltage is applied lead to changes in the spin properties of neighboring two-dimensional ferromagnets.

The lattice of the two-dimensional ferroelectric expands with voltage, changing the magnetic anisotropy of the adjacent ferromagnet and significantly reducing the coercivity required to reorient the spin. This means that by applying a very low voltage to a quantum material heterostructure device, it is possible to control the spin information of electrons even with a magnetic field reduced by about 70%, which is a key technology for the development of components with very low energy consumption. spin memory based on quantum materials.

“By obtaining ultra-low-power next-generation memory element technology using quantum materials, we will be able to maintain our technological lead and competitiveness in the recently declining semiconductor industry,” said the Dr. Jun Woo Choi of KIST.