Magnetization and spin resonances in helical spin systems

In this work, magnetization and magnetization dynamics in helical-ordered spin systems are considered. By employing the Nelder–Mead simplex numerical algorithm, the dependence of spin orientations on magnetic field is calculated for spin systems with arbitrary helicity. As demonstrated, in a certain case, the dependence of magnetization on magnetic field shows a clear dependence on helicity. Next, magnetization dynamics in helical-ordered spin systems with arbitrary helicity is studied by employing the Suhl–Smit–Beljers approach. Two types of resonance responses are examined: the molecular field response and collective spin resonance modes. Both types of responses also demonstrate clear dependence on helicity. Thus, it is demonstrated that the overall combination of magnetization measurements and ferromagnetic resonance studies defines the helical angle.