| 摘要 |
PURPOSE: To obtain a superconducting quantum interference device(SQUID) magnetometer which is capable of restraining a magnetic field distortion caused by an eddy current even if a cryostat is shielded, by a method wherein a shield prescribed in sheet resistance is provided. CONSTITUTION: A superconducting quantum interference device magnetometer 11 is equipped which a shielding sleeve which is formed of conductive shielding material and capable of shielding the magnetometer 11 from an interference electromagnetic field, wherein an unshielded cryostat 10 is completely surrounded with a shielding sleeve 19 which is set as high in sheet resistance as 50 to 70 mΘ/square and formed of, at least, a single layer of shielding material so as to avoid an increase in magnetometer noise as much as possible as a whole.
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