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A setup for element specific magnetization dynamics using the transverse magneto-optic Kerr effect in the energy
S Jana1, J A Terschlüsen1, R Stefanuik1
1Department of Physics and Astronomy, Molecular and Condensed Matter Physics, Uppsala University, P.O. Box 516, 75120 Uppsala, Sweden.
The Review of Scientific Instruments
|April 5, 2017
Summary
We developed a novel spectrometer for ultrafast magnetic material studies. This instrument enables faster, element-specific measurements of magnetic dynamics, improving upon previous research.
Area of Science:
- Materials Science
- Spectroscopy
- Condensed Matter Physics
Background:
- Ultrafast demagnetization studies require precise elemental analysis and temporal resolution.
- Existing methods for time-resolved magneto-optic Kerr effect (TR-MOKE) experiments can be time-consuming.
Purpose of the Study:
- To present a new spectrometer designed for element-specific, time-resolved TR-MOKE experiments.
- To achieve high temporal resolution (<40 fs) for studying magnetic dynamics.
- To enable simultaneous measurements across various magnetic transition metals.
Main Methods:
- Utilizing a Rowland-circle geometry spectrometer at the High Energy Laser Induced Overtone Source (HELIOS) facility.
- Employing high-harmonic generation (HHG) for pump-probe experiments with photon energies from 30-72 eV.
- Implementing features for easy sample handling, alignment, and rapid magnetic field switching.
Main Results:
- Successfully measured the ultrafast demagnetization of permalloy with high fidelity.
- Achieved comparable results to previous studies but with a 15% reduction in acquisition time.
- Observed a distinct shift in the demagnetization curve of Nickel relative to Iron.
Conclusions:
- The developed spectrometer offers an efficient and versatile tool for ultrafast magnetic material characterization.
- The observed Ni/Fe demagnetization shift provides further insight into element-specific magnetic relaxation dynamics.
- This advancement facilitates more rapid and detailed investigations into the transient magnetic properties of materials.
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