Development of high-speed polarizing imaging system for operation in high pulsed magnetic field

A high-speed polarizing microscope system combined with a 37 T pulse magnet has been developed. This system was applied to successfully visualize the field-induced collapse of charge-orbital ordering in a layered manganite $La1/2Sr3/2MnO4$⁠. Quantitative analyses of the obtained polarizing microscope images provided clear evidence of this transition in contrast to rather moderate changes in magnetization and magnetoresistance. The ability of this system to carry out quantitative analysis was further tested through the observation of Faraday rotation in a $Tb3Ga5O12$ crystal. The Verdet constant determined from the polarizing images is in reasonable agreement with that in literature. Local intensity analyses of the images indicate that we can investigate magneto-optical signals within an accuracy of 0.85% in an area of $9.6×9.6μm2$⁠.