A record-high trapped field of 5.6 T in the stacking of MgB₂/TiB₂ composite bulks prepared by an in-situ hot isostatic pressing method

We have studied the trapped field properties of triple and double stacking of $Mg{B}_2/Ti{B}_2$ composite superconductor bulks magnetized by field-cooled magnetization. The triple-stacked $Mg{B}_2/Ti{B}_2$ bulks trapped a magnetic field of 5.58 T successfully at 11.3 K, which was only 0.18 T but evidently higher than the world record trapped field of 5.4 T among $Mg{B}_2$ bulk magnets. We also found a potential ability of the present $Mg{B}_2/Ti{B}_2$ bulks trapping a 7-T class magnetic field at low temperatures below 4.2 K, although the FCM experiments at both 2.2 and 4.2 K were disturbed by the flux jumps. (paper)