Kerr ellipticity

There is no Kerr rotation or Kerr ellipticity for pure /flight or for mixed r- and p-light in the transverse geometry, but there is a magnetization induced change in the surface reflectivity. 

The sign of the Kerr ellipticity eK is defined as positive if the electric field of the reflected beam rotates in the same direction as the electric current that can be associated with the sample magnetization M, i.e. eK is positive if the rotation vector that can be associated with the handedness of the reflected polarization is parallel to M. The sign of the Kerr rotation polarization axis after reflection is parallel to M, too. 

Most of the theoretical models dealing with magneto-optical spectra pertain to the tensor elements 6. It follows therefore from the discussion given above that a meaningful interpretation of magneto-optical data can only be given if, in addition to the Kerr rotation experimental results are available for the complex dielectric constant er. 

Fig. 41. Calculated energy dependence of the dielectric constant and Kerr rotation K, eK of TmS at 2 K and B = 4 Tesla. The data were taken from results in the paper by Feil and Haas (1987).

Fig. 5.2-W Temperature dependence of magnetic ordering. Kerr ellipticity (representing bulk magnetization) and normalized polarization P/Po of scattered electrons in SPLEED (representing surface magnetization) as a function of T/Tc- The solid curves are fits to a Bloch law mi(0) — mi(T) = mi being the magnetization of...

Abe et al. (1982) studied the polar Kerr rotation, ellipticity and reflectivity in sputtered Co785Cr215 films. The energy range considered was 1.55-3.10 eV. The energy dependence of Kerr rotation is much reduced in the Co-Cr alloy if compared to Co metal. Abe et al. furthermore compared the results of their magneto-optical measurements with results of magnetization measurements. By means of this comparison they were able to show that the coercivity of the magnetization near the surface of the film is weaker than in the bulk of the material. 

Fig. 16. Energy dependence of the polar Kerr rotation

Fig. 21. Energy dependence of the Kerr rotation (

Fig. 22. Energy dependence of the Kerr rotation (

Fig. 27. Polar magneto-optical Kerr rotation

Fig. 36. Kerr rotation

Fig. 42. (a) Kerr rotation spectra of some R2Fe,4B compounds and of Fe metal, taken at room temperature in a field of 925 kA/m (11.6 kOe). By way of example the ellipticity (eK) of the Gd compound is also given, (b) Kerr rotation spectra of La2CouB and Gd2Co14B and of Co metal, taken at room temperature in a field of 925 kA/m (11.6 kOe). By way of example the ellipticity (fK) of the Gd compound is also given. (After van Engelen and Buschow 1986.)... 

The complex polar Kerr effect consists of both the rotation of polarization plane and the appearance of the ellipticity if a linearly polarized light reflects from a sample surface and the sample is magnetized normally to this surface (Figure 7.6a). If the light falls from the vacuum perpendicularly on the sample... 

Figure 1.1. The polar Kerr rotation (curve 1) and the ellipticity (curve 2) for EuO single crystal at 10K and H = 40kOe [31],...

The longitudinal (meridional) Kerr effect means both the rotation of polarization plane and appearance of the ellipticity when a linearly polarized light... 

M.D. Levenson, J.J. Song, Raman-induced Kerr effect with elliptical polarization. J. Opt. Soc. Am. 66,641 (1976)... 

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