Electrical excitation and detection of magnetic dynamics with impedance matching

TL;DR

This paper presents a technique for measuring microwave voltages generated by magnetization precession in high-resistance (Ga,Mn)As microbars, using impedance matching with a microstrip resonator to enhance measurement bandwidth and signal quality.

Contribution

The authors introduce a novel impedance matching method employing a microstrip resonator to improve microwave voltage detection in high-resistance magnetic microstructures.

Findings

Successful extraction of microwave voltages during magnetization precession

Enhanced measurement bandwidth and signal-to-noise ratio

Demonstration of impedance matching in high-resistance magnetic devices

Abstract

Motivated by the prospects of increased measurement bandwidth, improved signal to noise ratio and access to the full complex magnetic susceptibility we develop a technique to extract microwave voltages from our high resistance (10 k{\Omega}) (Ga,Mn)As microbars. We drive magnetization precession with microwave frequency current, using a mechanism that relies on the spin orbit interaction. A capacitively coupled lambda/2 microstrip resonator is employed as an impedance matching network, enabling us to measure the microwave voltage generated during magnetisation precession.