Numerical model of harmonic Hall voltage detection for spintronic devices

Abstract

We present a numerical macrospin model for harmonic voltage detection in multilayer spintronic devices. The core of the computational backend is based on the Landau-Lifshitz-Gilbert-Slonczewski equation, which combines high performance and satisfactory agreement with the experimental results in large-scale applications. We compare the simulations with the experimental findings in a Ta/CoFeB bilayer system for angular- and magnetic-field-dependent resistance measurements, electrically detected magnetization dynamics, and harmonic Hall voltage detection. Using simulated scans of the selected system parameters such as the polar angle $\ensuremath{\theta}$, magnetization saturation $({\ensuremath{\mu}}_{\text{0}}{M}_{\text{s}})$, or uniaxial magnetic anisotropy $({K}_{\text{u}})$, we show the resultant changes in the harmonic Hall voltage, demonstrating the dominating influence of the ${\ensuremath{\mu}}_{\text{0}}{M}_{\text{s}}$ on the first and second harmonics. In the spin-diode ferromagnetic resonance method, the $({\ensuremath{\mu}}_{\text{0}}{M}_{\text{s}},$ ${K}_{\text{u}})$ parameter space may be optimized numerically to obtain a set of viable curves that fit the experimental data.