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arXiv · 2005.00720

Lorentz microscopy and small-angle electron diffraction study of magnetic textures in La$_{1-x}$Sr$_x$MnO$_3$ (0.15 $< x <$ 0.30): the role of magnetic anisotropy

A. Kotani·H. Nakajima·K. Harada·Y. Ishii·S. Mori
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Abstract

Magnetic textures in the ferromagnetic phases of La$_{1-x}$Sr$_x$MnO$_3$ for 0.15 $< x <$ 0.30 have been investigated by Lorentz microscopy combined with small-angle electron diffraction experiments. Various types of magnetic textures characterized by stripe, plate-shaped, and cylindrical (magnetic bubble) domains were found. Two distinct types of magnetic stripe domains appeared in the orthorhombic structure with an inversion symmetry of La$_{0.825}$Sr$_{0.175}$MnO$_3$, depending significantly on magnetocrystalline anisotropy. Based on in-situ observations as functions of temperature and the strength of the external magnetic field, a magnetic field-temperature phase diagram was constructed, showing the stabilization of magnetic bubbles in the ferromagnetic phase of La$_{0.825}$Sr$_{0.175}$MnO$_3$.

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A. Kotani, H. Nakajima, K. Harada, Y. Ishii, S. Mori. 2020-05-02. Lorentz microscopy and small-angle electron diffraction study of magnetic textures in La$_{1-x}$Sr$_x$MnO$_3$ (0.15 $< x <$ 0.30): the role of magnetic anisotropy. https://doi.org/10.1103/physrevb.94.024407

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