Spintronic devices are made up of magnetic layers that act as spin polarisers or analysers separated by non-magnetic layers through which the spin-polarised electrons pass. Today, spintronics is considered to be one of the most important areas of emerging research with great promise and potential to deliver logic and memory electronic devices with high speed and low power consumption.
However, researchers are currently facing many challenges when it comes to developing efficient spintronics devices, one of which is achieving the electrical control of magnetic vortex dynamics in a reproducible and ultrafast way.
Now, physicists at Martin Luther University Halle-Wittenberg (MLU), together with colleagues from Lanzhou University in China, claim to have developed a concept that could significantly improve magnetic data processing. Their work was published in NPG Asia Materials in May.
Fast data processing concept. Pictured: a graphic that reflects improvements in the data handling speed of electronic devices. Image Credit: Pixabay.
Ultrashort Electrical Pulses
Magnetic data storage is a vital tool for securely storing all the data that we now produce day by day. Once stored, data can be left safely for several years without needing to be accessed. This makes it much better than, say, charge-based data storage (such as that currently used in mobile phones), because without an electrical charge, data storage can be short-lived.
Magnetic data storage is also much better than traditional magnetic hard drives, which are prone to mechanical failure and potentially irretrievable data losses as a result. They are also much slower and consume a lot more power.
A Viable Control Method
In their study, the researchers demonstrated a novel packaged-skyrmion-mediated vortex switching process that was driven by a simple sequence of picosecond (one trillionth of a second) electrical field pulses via magnetoelectric interactions. “We were after a fast and energy-efficient alternative,” explains Professor Jamal Berakdar from the Institute of Physics at MLU. By using these ultrashort pulses in the terahertz range, information could be written in magnetic nano-vortices and retrieved within picoseconds.
In theory, this means that billions of read and write operations could take place per second without the need for magnetic fields. “With the appropriately shaped pulses the data can be processed very quickly at low energy cost,” says Berakdar. The new concept is based on existing terahertz and magnetism technologies. “It exploits advances in electric pulse generation and nanomagnetism.”
In recent years, there have been many advances in generating and controlling electrical pulses. Therefore, according to the researchers, it makes sense to find ways to apply these pulses to data storage. To date, the method has been tested in computer simulations and their results demonstrate an energy-efficient, highly localised, and coherent control method for nonvolatile magnetic vortex-based information storage and handling.