A mechanical rotatable magnetic force microscope operated in a 7 T superconducting magnet

Tengfei Guo; Jihao Wang; Wenjie Meng; Jing Zhang; Qiyuan Feng; Ze Wang; Feng Jin; Wenbin Wu; Qingyi Lu; Yubin Hou; Qingyou Lu

doi:10.1016/j.ultramic.2020.113071

A mechanical rotatable magnetic force microscope operated in a 7 T superconducting magnet

Ultramicroscopy. 2020 Oct:217:113071. doi: 10.1016/j.ultramic.2020.113071. Epub 2020 Jul 16.

Authors

Tengfei Guo¹, Jihao Wang², Wenjie Meng², Jing Zhang², Qiyuan Feng², Ze Wang³, Feng Jin³, Wenbin Wu³, Qingyi Lu⁴, Yubin Hou⁵, Qingyou Lu⁶

Affiliations

¹ Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, AnHui 230031, China; Hefei National Laboratory for Physical Sciences at Microscale and Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, AnHui 230026, China.
² Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, AnHui 230031, China.
³ Hefei National Laboratory for Physical Sciences at Microscale and Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, AnHui 230026, China.
⁴ Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, JiangSu 210093, China; State Key Laboratory of Coordination Chemistry, School of Chemical Engineering. Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing JiangSu 210093, China.
⁵ Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, AnHui 230031, China. Electronic address: ybhou@hmfl.ac.cn.
⁶ Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, AnHui 230031, China; Hefei National Laboratory for Physical Sciences at Microscale and Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, AnHui 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, JiangSu 210093, China; Hefei Science Center Chinese Academy of Sciences, Hefei 230031, China. Electronic address: qxl@ustc.edu.cn.

PMID: 32717554
DOI: 10.1016/j.ultramic.2020.113071

Abstract

We present a mechanical rotatable magnetic force microscope (MFM) with precise angle control that can be operated in a 7 T superconducting magnet. An inertial piezoelectric motor called a SpiderDrive was used for the coarse approach because of its high compactness, high rigidity, and small size. Due to the mechanical rotation design, the MFM head can be rotated in a 7 T superconducting magnet with a bore size of 89 mm so that the direction of the magnetic field can be changed from 0° to 90° continuously. The highest in-plane magnetic field strength tested was 7 T. This is the first rotatable MFM ever reported. Using the homemade rotatable MFM, we investigated a 40 nm thick La_0.67Ca_0.33MnO₃ (LCMO) thin film on NdGaO₃ (100) substrate with anisotropy, determining that the charge-ordering insulating (COI) phase of the LCMO disappears as the direction of the magnetic field changed from 0° to 90°. Furthermore, the ferromagnetic pattern, appearing as bright and dark contrasts and similar to that formed by the S and N of a magnet, was seen parallel to the direction of the magnetic field. The rotatable MFM in this paper is expected to be widely used in studying the anisotropy of magnetic materials.

Keywords: Anisotropy; High magnetic field; In-pane magnetic field; Magnetic force microscope; Superconducting magnet.