Development of a magneto-optical Kerr microscope using a 3D printer

Abstract

Background Magneto-optical Kerr effect (MOKE) microscopes are powerful experimental tools to observe magnetic domains in magnetic materials. These devices are, however, typically large, unportable, and expensive (∼ several million yen), and therefore prevent many researchers in the field of materials science from easy access to study real-space images of magnetic domains. Methods To overcome these issues, we utilized data from “The OpenFlexure Project” developed by the University of Bath and the University of Cambridge. The purpose of this project is to make high-precision mechanical positioning of the studied sample available to anyone with a 3D printer, especially for use in microscopes. We built a low-cost and portable MOKE microscope device with a 3D printer. We redesigned the 3D modeling data of an ordinary optical microscope provided by The OpenFlexure project and incorporated additional elements, such as optical polarizers and an electromagnetic coil into the primarily designed microscope that did not originally have these elements. Results We successfully observed magnetic domains and their real-space motions induced by magnetic fields using the palm-sized low-cost MOKE microscope, which costs approximately 30,000 yen in raw materials to construct. Conclusions Our methodology to assemble a low-cost MOKE microscope will enable researchers working in the field of materials science to observe magnetic domains more easily without commercial equipment.