Free-standing and positionable microwave antenna device for magneto-optical spectroscopy experiments
arXiv:1911.11517 · doi:10.1103/PhysRevApplied.13.054009
Abstract
Modern spectroscopic techniques for the investigation of magnetization dynamics in micro- and nano- structures or thin films use typically microwave antennas which are directly fabricated on top of the sample by means of electron-beam-lithography (EBL). Following this approach, every magnetic structure on the sample needs its own antenna, resulting in additional EBL steps and layer deposition processes. We demonstrate a new approach for magnetization excitation that is suitable for optical and non-optical spectroscopy techniques. By patterning the antenna on a separated flexible glass cantilever and insulating it electrically, we solved the before mentioned issues. Since we use flexible transparent glass as a substrate, optical spectroscopy techniques like Brillouin-light-scattering microscopy (μBLS), time resolved magneto-optical Kerr effect measurements (TRMOKE) or optical detected magnetic resonance (ODMR) measurements can be carried out at visible laser wavelengths. As the antenna is detached from the sample it can be freely positioned in all three dimensions to adress only the desired magnetic sample structures and to achieve effective excitation. We demonstrate the functionality of these antennas using μBLS and compare coherently and thermally excited magnon spectra to show the enhancement of the signal by a factor of about 400 due to the excitation by the antenna. Moreover, we succeed to characterize yttrium iron garnet thin films with spatial resolution using optical ferromagnetic resonance (FMR) experiments. We analyse the spatial excitation profile of the antenna by measuring the magnetization dynamics in two dimensions. The technique is furthermore applied to investigate injection-locking of spin Hall nano-oscillators.
References in corpus (12)
- Spin Hall effect
- Microwave Oscillations of a Nanomagnet Driven by a Spin-Polarized Current
- Perspective: Ultrafast magnetism and THz spintronics
- Nanowire Spin Torque Oscillator Driven by Spin Orbit Torques
- Nanoscale magnetophotonics
- Ferroic collinear multilayer magnon spin valve
- On the origin of magnetization auto-oscillations in constriction-based spin Hall nano-oscillators
- Quantification of a propagating spin-wave-packet created by an ultrashort laser pulse in a thin film of magnetic metal
- Combined frequency and time domain measurements on injection-locked, constriction-based spin Hall nano-oscillators
- Zero-field propagation of spin waves in waveguides prepared by focused ion beam direct writing
- Optimizing propagating spin wave spectroscopy
- Time resolved imaging of the non-linear bullet mode within an injection-locked nano-contact spin Hall nano-oscillator