May 14 2019
The ever-growing demand for energy and the fundamental limits on miniaturization have hindered further progresses in IT technologies. Another challenge is energy dissipation, which mostly goes into warming up the environment.
Physicists at Martin Luther University Halle-Wittenberg (MLU) and Lanzhou University in China recently discovered a new type of spin waves, which may help in overcoming these challenges.
Existing technologies for transferring and processing information are hindered by fundamental physical limits. The more powerful they turn out to be, the more energy they require and more heat is liberated into the environment. Moreover, there are physical limits on the efficiency and size of communication devices.
The latest discovery provides a new technique for achieving advancements in these problems. They have explained about a new type of spin waves in the most recent edition of the Nature Communications, which can be employed to transmit and process information with significantly lower energy consumption and higher efficiency.
Traditional IT applications work based on electric charge currents. “This results inevitably in energy losses heating up the environment” stated MLU physicist Professor Jamal Berakdar. He further stated that more energy is required and also released to operate more compact and powerful devices. Therefore, it is very hard to maintain the advancement pace using technology that is based on charge current. As part of the research, the groups headed by Professor Berakdar and Professor Chenglong Jia of Lanzhou University thus investigated alternative concepts for data communication and processing.
Their study was about the so-called magnons.
These are waves that are stimulated in ferromagnets by just a fraction of the energy needed for generating the required charge currents. Magnons can be used to transmit signals and for logical operations in various components while producing virtually no heat.
Jamal Berakdar, Professor, MLU
In the latest study, the German-Chinese research group explained about a kind of twisted magnons for which the winding number or the twist is protected against damping.
In technical terms, the twist is associated with magnon orbital angular momentum. It is feasible to control the orientation and magnitude of the twist using electric voltages. This opens the door for a multiplex twist-based signal encoding and transmission over huge distances.
The researchers report that the study outcomes pave the way for the transmission of high-density information through magnons. Apart from the energy efficiency, the wavelengths of the magnons are short and controllable than those of optical waves, which itself is beneficial for miniaturization. It is also possible to integrate magnonic elements in prevalent technologies.
This study was supported by the National Natural Science Foundation of China (Nos. 11474138 and 11834005), the German Research Foundation (No. SFB 762 and SFB TRR 227), and the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT-16R35).