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arXiv · 2003.12768

Optical imaging of antiferromagnetic domains in ultrathin CoO(001) films

Jia Xu·Haoran Chen·Chao Zhou·Dong Shi·Gong Chen·Yizheng Wu
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Abstract

Antiferromagnetic (AFM) domains in ultrathin CoO(001) films are imaged by a wide-field optical microscopy using magneto-optical birefringence effect. The magnetic origin of observed optical contrast is confirmed by the spin orientation manipulation through exchange coupling in Fe/CoO(001) bilayer. The finite size effect of ordering temperature for ultrathin single crystal CoO film is revealed by the thickness and temperature dependent measurement of birefringence contrast. The magneto-optical birefringence effect is found to strongly depend on the photon energy of incident light, and a surprising large polarization rotation angle up to 168.5 mdeg is obtained from a 4.6 nm CoO film with a blue light source, making it possible to further investigate the evolution of AFM domains in AFM ultrathin film under external field.

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Jia Xu, Haoran Chen, Chao Zhou, Dong Shi, Gong Chen, Yizheng Wu. 2020-03-28. Optical imaging of antiferromagnetic domains in ultrathin CoO(001) films. https://doi.org/10.1088/1367-2630%2Faba1b4

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