Dynamic detection of electron spin accumulation in ferromagnet–semiconductor devices by ferromagnetic resonance

Abstract

A distinguishing feature of spin accumulation in ferromagnet–semiconductor devices is its precession in a magnetic field. This is the basis for detection techniques such as the Hanle effect, but these approaches become ineffective as the spin lifetime in the semiconductor decreases. For this reason, no electrical Hanle measurement has been demonstrated in GaAs at room temperature. We show here that by forcing the magnetization in the ferromagnet to precess at resonance instead of relying only on the Larmor precession of the spin accumulation in the semiconductor, an electrically generated spin accumulation can be detected up to 300 K. The injection bias and temperature dependence of the measured spin signal agree with those obtained using traditional methods. We further show that this approach enables a measurement of short spin lifetimes (<100 ps), a regime that is not accessible in semiconductors using traditional Hanle techniques.

Reduced interface spin polarization by antiferromagnetically coupled Mn segregated to the Co2MnSi /GaAs (001) interface

“…CMS is also well-suited to devices, because it is lattice matched to GaAs semiconductor channels and MgO tunnel barriers. Estimates of the interfacial spin polarization in various devices range up to 89% at low temperature 20 , with lower and widely varying values reported at room temperature 21,22,24,26,27 .…”

“…This large discrepancy was attributed to atomic disorder in the CMS lattice due to a chemical reaction at the GaAs interface. More recently, several groups have synthesized CMS thin films on GaAs and incorporated them into spintronic devices 14,[26][27][28][29] .…”

Role of exchange interaction in nitrogen vacancy center based magnetometry

“…FMH have been used as a platform for practical spintronic devices, such as spinHall [1][2][3][4][5] and spin-orbit-based memories [6][7][8], anomalous Hall, and topological Hall-based sensors [9]. In such systems, the spin density can be detected by many methods, such as magneto-optic Kerr effect (MOKE) [10,11], ferromagnetic resonance (FMR) [12], and electrical measurements [13,14]. In the characterization of the FMH devices, a spatial resolution of the spin distribution up to the order of µm has been achieved by MOKE [11], and up to sub-µm using magnetic force microscopy (MFM) [15].…”

Effect of Zn substitution in (111)-textured ZnxFe3−xO4 thin films on magnetization dynamics

“…Ferromagnetic resonance (FMR) is a powerful experimental technique for studying the magnetic properties of thin films [12,13]. It can provide sufficient information describing the magnetic properties, such as effective magnetization, magnetic anisotropy, gyromagnetic ratio, especially magnetization dynamic damping from FMR linewidth.…”