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Thomas Mühl

t.muehl (et) ifw-dresden.de

Welcome to our

Magnetism on the nanoscale lecture!

Today:

Magnetic Microscopy

How to image/characterize nanomagnets or nanomagnetic configurations?

Question to you: Which magnetism-related interactions might be used to image magnetic properties?

(Please use public chat in BigBlueButton)

Interaction Microscopy method

Magnetic Force Microscopy (MFM)

Magnetic Force Microscopy

SEM

Source: Nielsch et al., JMMM 249, 234 (2002)

New types of MFM sensors

Source: Reiche, Mühl et al., New J.

Phys. 17, 013014 (2015)

MFM

Magneto-Optical Kerr Microscopy

Magneto-Optical Kerr Microscopy

Source: Hubert, Schäfer, Magnetic Domains, Springer 1998

before After contrast enhancement

Amorphous iron-nickel alloy

After quantitative evaluation(combining two digital images)

Photoemission Electron Microscopy (PEEM) with X-ray Magnetic Dichroism (XMCD)

Source: http://www.physik.fu-berlin.de/einrichtungen/ag/ag-

kuch/research/techniques/peem/index.html

Photoemission Electron Microscopy (PEEM) with X-ray Magnetic Dichroism (XMCD)

Source: Li et al., Nature Comm. (2014) DOI: 10.1038/ncomms5704

Source: http://www.physik.fu-berlin.de/einrichtungen/ag/ag-

kuch/research/techniques/peem/index.html

Co dot

XMCD Co PEEM

Photoemission Electron Microscopy (PEEM) with X-ray Magnetic Dichroism (XMCD)

Ni film

Lorentz Transmission Electron Microscopy

Source: Hubert, Schäfer, Magnetic Domains, Springer 1998

Lorentz Transmission Electron Microscopy

Question to the audience: Where do we expect Lorentz TEM contrast?

Source: Hubert, Schäfer, Magnetic Domains, Springer 1998

Lorentz Transmission Electron Microscopy

Source: Yu, Tokura et al., Nature 465, 901 (2010)

Magnetic skyrmions

Fe0.5Co0.5Si thin film (imaged by Lorentz TEM)

Further magnetic microscopy techniques:

Scanning probe based

• Magnetic resonance force microscopy

• Magnetic exchange force microscopy

• Spin-polarized scanning tunneling microscopy (SP-STM)

• Magnetic microscopy using nitrogen-vacancy probes

• Scanning Hall probe microscopy

Electron-beam based

• TEM-based electron holography

• Scanning electron microscopy with polarization analysis (SEMPA)

Thank you very much for your interest and also for all interactions during our online lecture.

In case of questions please do not hesitate to get in touch with me.

Best regardsThomas