Nonlinear thermal effect on sub-gigahertz ferromagnetic resonance in magnetic tunnel junction
Abstract
Sub-gigahertz ferromagnetic resonance (FMR) is investigated in a magnetic tunnel junction (MTJ) with small anisotropy fields. Distinct FMR spectra down to 0.36 GHz are obtained by applying an external field that cancels out the anisotropy. A macrospin model simulation reveals that the difficulty in obtaining a smaller frequency excitation is not due to a magnetization inhomogeneity mainly attributed to domain creation but to a nonlinear thermal effect. The results indicate that anisotropy engineering through interfacial magnetic anisotropy together with voltage control will assist in realizing MTJs for low-frequency spin-torque devices.
- Publication:
-
Applied Physics Letters
- Pub Date:
- July 2013
- DOI:
- 10.1063/1.4816357
- Bibcode:
- 2013ApPhL.103d2404M
- Keywords:
-
- ferromagnetic resonance;
- magnetic anisotropy;
- magnetic tunnelling;
- 76.50.+g;
- 75.30.Gw;
- 75.70.Cn;
- Ferromagnetic antiferromagnetic and ferrimagnetic resonances;
- spin-wave resonance;
- Magnetic anisotropy;
- Magnetic properties of interfaces