Magnonic logic devices

Background and Objectives: There is a big impetus for the development of novel computational devices able to overcome the limits of the traditional transistor-based circuits. The utilization of phase in addition to amplitude is one of the promising approaches towards more functional computing architectures. In this work, we present an overview on magnonic logic devices utilizing spin waves for information transfer and processing. Materials and Methods: Magnonic logic devices combine input/output elements for spin wave generation/detection and an analog core. The core consists of magnetic waveguides serving as a spin wave buses. The data transmission and processing within the analog part is accomplished by the spin waves, where logic 0 and 1 are encoded into the phase of the propagating wave. The latter makes it possible to utilize spin wave interference for logic functionality. The proof-of-concept experiments were accomplished on micrometer scale ferromagnetic Ni$_81$Fe$_19$ and ferrite Y$_3$Fe$_2$(FeO$_4$)$_3$ structures. Results: We present experimental data on spin wave propagation and interference in magnetic microstructures. We also present experimental data showing parallel read-out of magnetic bits using spin wave interference. Based on the obtained results, we consider possible logic circuits and architectures. Conclusion: Magnonic logic devices may offer a significant functional throughput enhancement over the conventional logic circuits by exploiting phase in additi on to amplitude. It is also possible to construct non-volatile magnonic logic circuits with built-in magnetic memory. Magnonic logic devices such as magnonic holographic memory are aimed not to replace but to complement the existing logic circuitry in special task data processing.