Spin wave excitation patterns generated by spin torque oscillators

TL;DR

This paper demonstrates how arrays of spin torque nano oscillators can generate controllable, directional spin-wave radiation and interference patterns, offering new possibilities for on-chip communication and spin wave research.

Contribution

It introduces a method to create and control directional spin-wave patterns using STNO arrays, advancing spin wave manipulation techniques.

Findings

Arrays of STNO produce directional spin-wave radiation.

Interference patterns depend on wavelength and phase of emitted spin waves.

Active control of spin-wave patterns is achievable via direct current.

Abstract

Spin torque nano oscillators (STNO) are nano-scale devices that can convert a direct current into short wave-length spin-wave excitations in a ferromagnetic layer. We show that arrays of STNO can be used to create directional spin-wave radiation similar to electromagnetic antennas. Combining STNO excitations with planar spin waves also creates interference patterns. We show that these interference patterns are static and have information on the wavelength and phase of the spin waves emitted from the STNO.We describe means of actively controlling spin-wave radiation patterns with the direct current owing through STNO, which is useful in on-chip communication and information processing and could be a promising technique for studying short wave-length spin waves in different materials.