The rapid rise in AI applications has placed increasingly heavy demands on our energy infrastructure. All of the more reason to seek out energy-saving solutions for AI hardware. One promising idea is using so-called spin waves to process information. A team from the Universities of Münster and Heidelberg (Germany) led by physicist Prof. Rudolf Bratschitsch (Münster) has now developed a brand new technique to produce waveguides wherein the spin waves can propagate particularly far. They’ve thus created the most important spin waveguide network to this point. Moreover, the group succeeded in specifically controlling the properties of the spin wave transmitted within the waveguide. For instance, they were capable of precisely alter the wavelength and reflection of the spin wave at a certain interface. The study was published within the scientific journal Nature Materials.
The electron spin is a quantum mechanical quantity that can also be described because the intrinsic angular momentum. The alignment of many spins in a cloth determines its magnetic properties. If an alternating current is applied to a magnetic material with an antenna, thereby generating a changing magnetic field, the spins in the fabric can generate a spin wave.
Spin waves have already been used to create individual components, resembling logic gates that process binary input signals into binary output signals, or multiplexers that select certainly one of various input signals. Up until now, nonetheless, the components weren’t connected to form a bigger circuit. “The undeniable fact that larger networks resembling those utilized in electronics haven’t yet been realised, is partly on account of the strong attenuation of the spin waves within the waveguides that connect the person switching elements – especially in the event that they are narrower than a micrometre and due to this fact on the nanoscale,” explains Rudolf Bratschitsch.
The group used the fabric with the bottom attenuation currently known: yttrium iron garnet (YIG)., The researchers inscribed individual spin-wave waveguides right into a 110 nanometre thin film of this magnetic material using a silicon ion beam and produced a big network with 198 nodes. The brand new method allows complex structures of top of the range to be produced flexibly and reproducibly.
The German Research Foundation (DFG) funded the project as a part of the Collaborative Research Centre 1459 “Intelligent Matter.”