Record-High Trapped Magnetic Field by Pulse Field Magnetization Using GdBaCuO Bulk Superconductor

A trapped magnetic field B T P as high as 4.47 T, which is the highest reported using pulse field magnetization to date, has been realized on the surface of a GdBaCuO bulk superconductor by a modified multi pulse technique combined with stepwise cooling. Following an introduction of a small amount magnetic flux into the bulk center by applying lower pulse fields B ex =4.5–4.6 T twice at a higher starting temperature T s =45–48 K, higher fields of B ex =6.6–6.7 T are applied three times at a lower T s =28–29 K. The reduction in the temperature rise due to the already existing trapped flux, in addition to the optimization of the higher B ex value at the lower T s , is a key point in enhancing B T P .