Determination of magneto-optical constants by measuring Kerr rotation angles of magnetic films with different sample structures

Zheng, R. T., Xu, X. W., Liang, X. A., Lum, Z. A.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

R. T. Zheng, X. W. Xu, X. A. Liang, Z. A. Lum Determination of magneto-optical constants by measuring Kerr rotation angles of magnetic films with different sample structures [на англ. яз.] // Оптический журнал. 2016. Т. 83. № 2. С. 73–78.

R. T. Zheng, X. W. Xu, X. A. Liang, Z. A. Lum Determination of magneto-optical constants by measuring Kerr rotation angles of magnetic films with different sample structures [in English] // Opticheskii Zhurnal. 2016. V. 83. № 2. P. 73–78.

For citation (Journal of Optical Technology):

R. T. Zheng, X. W. Xu, X. A. Liang, and Z. A. Lum, "Determination of magneto-optical constants by measuring Kerr rotation angles of magnetic films with different sample structures," Journal of Optical Technology. 83(2), 132-136 (2016). https://doi.org/10.1364/JOT.83.000132

Abstract:

A new data analysis method is proposed to determine magneto-optical (MO) constants by measuring Kerr rotation angles on samples with different multilayer film structures. The MO film in the multilayer samples is protected by a SiO₂ film with two different thicknesses. An existing algorithm is used to calculate the Kerr rotation angle based on the MO theory developed in the early 1990s. A new error function is defined to evaluate the distance from the calculated Kerr angles to the measured ones. The proposed method is developed based on the Staged Continuous Tabu Search (SCTS) algorithm to retrieve the MO constant by searching the minimum of the error function. The uniqueness and accuracy of the MO constant determined by this method are discussed, and its relative error introduced by the measurement error of Kerr rotation angles is also analyzed. Without measuring the ellipticity, the proposed method is relatively simple and can be applied to determine the MO constants for the samples with two or three layers of films.

Keywords:

magneto-optical constant; Kerr rotation angle; multilayer film structure; data analysis

OCIS codes: 310.3915, 310.5448, 310.6845, 310.6860, 310.5696

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