Probing magnetic microtextures on the nanoscale

Datum

18.01.2019

Zeit

13:00 - 14:00

Sprecher

Dr. Volker Neu

Zugehörigkeit

IFW Dresden

Sprache

en

Hauptthema

Materialien

Andere Themen

Materialien, Physik

Host

Kristina Krummer

Beschreibung

Magnetic force microscopy (MFM) has established its place as an extremely valuable method for the investigation of magnetic microstructures on the nanometer scale. Beyond being a purely qualitative imaging technique, quantitative MFM has the capability to locally measure the stray fields and eventually provide quantitative input data for a reconstruction of the underlying magnetization structure. This requires a full calibration of the imaging properties of the MFM tip and the most general approach is through the determination of the so-called tip transfer function (TTF) in Fourier space [1-3]. A calibrated tip transforms MFM signals into true stray field values on the nanometer scale. Furthermore, the field profile is corrected for the tip broadening and thus allows a true size determination of isolated magnetic objects. Reconstructing the magnetization texture from the stray field landscape will need additional knowledge on the sample. Here, micromagnetic simulations can help by providing valid initial magnetization models. I will report on our activities within a current European metrology project [4] to establish materials, measurement protocols and analysis procedures for a routine application of qMFM and will present various examples, which demonstrate the large benefit of treating MFM data quantitatively. These examples range from vortex states at nanowires and thin films to flux lines in superconductors and to optically written domains in magnetic data storage media [5]. [1] Hug et al. JAP 83 (1998), [2] Vock et al. APL 105 (2014), [3] Panchal et al. Sci. Rep. 7 (2017). [4] EMPIR 15SIB06 NanoMag [5] John et al., Sci. Rep. 7 (2017).

Links

• Seminars at the IFW

Letztmalig verändert: 18.01.2019, 01:09:40