Effect and Solution of Residual Magnetic Field of High Field Superconducting Magnet on Low Field Magnetic Measurement

The superconducting magnets that provide the strong magnetic field in physical property measurement system commonly used for magnetic measurements use non-ideal Type II superconductors. The artificially introduced "defects" can effectively improve the tolerance of superconductors to magnetic fields, allowing superconducting magnets to carry more currents and generate higher magnetic fields. However, the superconducting magnets generate residual magnetic fields during demagnetization, which can seriously affect the test results under lower magnetic field conditions. Through theoretical analysis and practical measurement, the effects of Oscillate mode and Linear mode on the residual magnetic fields were compared when the magnetic field was set to zero. It was found that the Oscillate mode significantly reduces the residual magnetic field and facilitates magnetic testing at lower magnetic field conditions.