Comparison of the use of NiFe and CoFe as electrodes for metallic lateral spin-valves

TL;DR

This study compares NiFe and CoFe electrodes in metallic lateral spin-valves, showing CoFe significantly enhances spin signal amplitude due to higher effective polarization, at both room and low temperatures.

Contribution

It provides a comparative analysis of NiFe and CoFe electrodes, demonstrating CoFe's superior performance in increasing spin signal amplitude in lateral spin-valves.

Findings

CoFe electrodes increase spin signal amplitude by up to tenfold.

The spin signal depends on electrode separation, modeled by 1D and finite element simulations.

Higher effective polarization in CoFe explains the enhanced spin signals.

Abstract

Spin injection and detection in Co60Fe40-based all-metallic lateral spin-valves have been studied at both room and low temperatures. The obtained spin signals amplitudes have been compared to that of identical Ni80Fe20-based devices. The replacement of Ni80Fe20 by CoFe allows increasing the spin signal amplitude by up to one order of magnitude, thus reaching 50 m{\Omega} at room temperature. The spin signal dependence with the distance between the ferromagnetic electrodes has been analyzed using both a 1D spin transport model and finite elements method simulations. The enhancement of the spin signal amplitude when using CoFe electrodes can be explained by a higher effective polarization.