Magnon dispersion in the spintronic alloys Co50Fe50 and Co20Fe60B20

Co50Fe50 (CF) and Co20Fe60B20 (CFB) have generated a lot of interest in the spintronics/magnonics/spin caloritronics community due to their hard magnetic nature, low magnon linewidth and ease of thin film fabrication. We have studied the spin Seebeck effect (SSE) in Si/CF/Pt and Si/CFB/Pt thin films and have obtained large thermomagnetic responses showing promise for energy harvesting applications. Since the SSE is governed by magnon propagation, it is important to study low and high energy magnon modes for determining SSE efficiency. We have measured the low energy magnon modes in these films using ferromagnetic resonance and have obtained low magnon damping. We now aim to study the high energy magnon propagation in CF and CFB powders using inelastic neutron scattering on the MAPS instrument to form a complete picture of the SSE in these materials and aid in technological applications.