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arXiv · 2201.11744

Measurement of DC Magneto-Optical Kerr Effect with Sensitivity of $10^{-7} \text{Rad}/\sqrt{\text{Hz}}$

Junying Ma·Feng Gu·Ying Xu·Jiaming Le·Fanlong Zeng·Yizheng Wu·Chuanshan Tian
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Abstract

A high-sensitive DC Magneto-Optical Kerr Effect (MOKE) apparatus is described in this letter. Via detailed analysis on several dominating noise sources, we have proposed solutions that significantly lower the MOKE noise, and a sensitivity of $1.5\times10^{-7} \text{rad}/\sqrt{\text{Hz}}$ is achieved with long-term stability. The sensitivity of the apparatus is tested by measuring a wedge-shaped Ni thin film on $\text{SiO}_2$ with Ni thickness varying from 0 to 3 nm. A noise floor of $1.5\times10^{-8}$ rad is demonstrated. The possibility of further improving sensitivity to $10^{-9}$ rad via applying ac modulation is also discussed.

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Junying Ma, Feng Gu, Ying Xu, Jiaming Le, Fanlong Zeng, Yizheng Wu, Chuanshan Tian. 2022-01-27. Measurement of DC Magneto-Optical Kerr Effect with Sensitivity of $10^{-7} \text{Rad}/\sqrt{\text{Hz}}$. https://arxiv.org/abs/2201.11744

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