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arXiv · 2311.08529

Visualizing thickness-dependent magnetic textures in few-layer $\text{Cr}_2\text{Ge}_2\text{Te}_6$

Andriani Vervelaki·Kousik Bagani·Daniel Jetter·Manh-Ha Doan·Tuan K. Chau·Boris Gross·Dennis Christensen·Peter Bøggild·Martino Poggio
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Abstract

Magnetic ordering in two-dimensional (2D) materials has recently emerged as a promising platform for data storage, computing, and sensing. To advance these developments, it is vital to gain a detailed understanding of how the magnetic order evolves on the nanometer-scale as a function of the number of atomic layers and applied magnetic field. Here, we image few-layer $\text{Cr}_2\text{Ge}_2\text{Te}_6$ using a combined scanning superconducting quantum interference device and atomic force microscopy probe. Maps of the material's stray magnetic field as a function of applied magnetic field reveal its magnetization per layer as well as the thickness-dependent magnetic texture. Using a micromagnetic model, we correlate measured stray-field patterns with the underlying magnetization configurations, including labyrinth domains and skyrmionic bubbles. Comparison between real-space images and simulations demonstrates that the layer dependence of the material's magnetic texture is a result of the thickness-dependent balance between crystalline and shape anisotropy. These findings represent an important step towards 2D spintronic devices with engineered spin configurations and controlled dependence on external magnetic fields.

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Andriani Vervelaki, Kousik Bagani, Daniel Jetter, Manh-Ha Doan, Tuan K. Chau, Boris Gross, Dennis Christensen, Peter Bøggild, Martino Poggio. 2023-11-14. Visualizing thickness-dependent magnetic textures in few-layer $\text{Cr}_2\text{Ge}_2\text{Te}_6$. https://doi.org/10.1038/s43246-024-00477-5

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