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arXiv · 2501.08108

Compact pulsed laser deposition system for in-situ polarized neutron reflectometry

Grigorii Kirichuk·Alexey Grunin·Artur Dolgoborodov·Pavel Prokopovich·Petr Shvets·Alexey Vorobiev·Anton Devishvilli·Alexandr Goikhman·Ksenia Maksimova
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Abstract

The development of ferromagnet/heavy metal thin-film structures, such as CoFeB/Mo, with spin-orbit interaction requires advanced methods for their production and study. Polarized neutron reflectometry (PNR) provides unique insights into the evolution of magnetic properties, especially when applied in-situ during the growth process. Pulsed laser deposition (PLD) is a versatile method for producing magnetic thin films, and combining PLD with in-situ PNR measurements offers new possibilities for their investigation. In this work, we developed a compact vacuum chamber integrated into the neutron instrument, enabling step-by-step deposition and in-situ PNR measurements. A multilayer Mo/[CoFeB/Mo]12 structure was grown, and neutron reflectivity curves measured after each cycle revealed the gradual evolution of sample properties. A weak magnetic field response suggested the potential formation of perpendicular magnetic anisotropy (PMA) at CoFeB/Mo interfaces. Additionally, a single CoFeB film was annealed up to 450°C, followed by the deposition of a ~5 Å Mo layer. PNR measurements in magnetic fields of 0.01 T and 0.75 T showed a significant increase in in-plane magnetization, confirming PMA formation. Thus, we demonstrate the first successful operation of a combined PLD and in-situ PNR system, showcasing its capabilities for characterizing single-layer CoFeB and multilayer CoFeB/Mo thin-film structures.

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Grigorii Kirichuk, Alexey Grunin, Artur Dolgoborodov, Pavel Prokopovich, Petr Shvets, Alexey Vorobiev, Anton Devishvilli, Alexandr Goikhman, Ksenia Maksimova. 2025-01-14. Compact pulsed laser deposition system for in-situ polarized neutron reflectometry. https://doi.org/10.1016/j.vacuum.2025.114521

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