Open AccessInhomogeneous field calibration of a magneto-optical indicator film device
Author(s) -
Manuela Gerken,
S. Sievers,
H. W. Schumacher
Publication year - 2020
Publication title -
measurement science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.48
H-Index - 136
eISSN - 1361-6501
pISSN - 0957-0233
DOI - 10.1088/1361-6501/ab816e
Subject(s) - calibration , magnetometer , magnetic field , demagnetizing field , characterization (materials science) , optics , materials science , image resolution , magnet , electromagnet , field (mathematics) , hall effect sensor , physics , magnetization , mathematics , quantum mechanics , pure mathematics
A concept for the traceable calibration of magneto-optical indicator film (MOIF) based magnetic field imaging devices is presented and discussed for the example of a commercial MOIF device with a 60 × 45 mm 2 sensor. The calibration facilitates a quantitative and fast characterization of magnetic microstructures combining relatively high spatial resolution with large imaging areas. The macroscopic calibration is performed using the homogeneous magnetic stray field of a pre-characterized electromagnet with a large pole shoe diameter of 250 mm. However, this calibration alone cannot yet account for the vectorial and spatially fast decaying stray fields of magnetic microstructures. For that, a forward simulation approach is pursued, based on the temperature-dependent magnetic parameters of the MOIF material as resulting from superconducting quantum interference device magnetometry and ferromagnetic resonance measurements. This is complemented by a transfer function-based approach to correct the impact of the sensor thickness and in-plane stray field components. The validity of the combined calibration and simulation approach is proven by means of a quantitative characterization of a magnetic scale. For the commercial MOIF device a 28.4 µm spatial resolution and 1.18 mT field resolution is achieved. The calibration is validated by a comparison to scanning Hall probe microscopy results. Furthermore, the uncertainty budget is discussed.