Interacting Magnonic Currents and Chiral Spin Textures for Energy Efficient Spintronics

• Applicant: Dr. Helmut Schultheiß
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 410406067

Spintronics is one of the cutting-edge topics in condensed matter physics which aim to harness the spin degree of freedom of electrons for information science that has formed a new discipline - spintronics. Based on charge transport phenomena of spin polarized electrons, spintronics, has made its leap in data storage by providing extremely sensitive detectors in magnetic hard drives and turned out to be challenging to communicate spin information without great losses. On the other hand, magnonics which is so far a visionary concept, utilize magnons - the collective excitation of spins, as information carriers are advantageous for energy efficient electronics. Magnons are waves of the electrons’ spin precessional motion in magnetically ordered materials that propagate without actual charge transport and its associated Ohmic losses, paving the way for a substantial reduction of energy consumption in computers. Another exciting topic appeared recently in spintronics community is magnetic skyrmion. Magnetic skyrmions are topologically protected chiral spin textures with unique real-space topological properties and great potential in data storage. Aiming in taking advantages of these two topics: we propose to study the link between magnonics and skyrmionics for energy efficient spintronics.Our proposal is motivated by the facts that both magnons and chiral spin textures share a common ground set by the interplay of dipolar, spin-orbit and exchange energies rendering them perfect interaction partners. Magnons are fast, sensitive to the spins’ directions and easily driven far from equilibrium. Chiral spin textures are robust, non-volatile and still reprogrammable on ultrashort timescales. By using magnetron sputtering, phase/momentum resolved Brillouin light scattering (BLS) spectroscopy, spin sensitive imaging techniques, our strategy is the following: (I) we will utilize the asymmetric scattering between magnon (spin-wave) and chiral spin textures for optimizing the non-collinear Dzyaloshinskii-Moriya interaction and hence skyrmion materials, (II) we will fabricate nanoscale devices to test the mutual interaction between magnons and skyrmions, through which the novel phenomena such as magnonic spin transfer torque, magnonic topological Hall effect. A success of the proposed research could thus provide vast possibilities for combining the toolset of magnetic phenomena, adding important value to both magnonics and the fundamental understanding of complex topological spin textures and establish an avenue for energy efficient spintronics.

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: National Natural Science Foundation of China
• Cooperation Partner: Professor Dr. Wanjun Jiang