We measured ¹H nuclear magnetic resonance (NMR) spectra from silicon rubber in a magnetic field trapped by a compact tubular MgB₂ superconductor bulk magnet (60 mm outer diameter, 40 mm inner diameter, and 60 mm height) which was magnetized by field-cooled magnetization from an applied field, , of 0.4778 T at 20 K. The sharpest ¹H NMR spectrum of the resonant frequency, , of 20.314 MHz, which corresponded to a field strength of 0.4771 T, was observed at 1 mm below the center of the bore of the MgB₂ tube. The homogeneity of the trapped field was within 100 ppm between z −2 and +2 mm along the central z-axis, which was evaluated by the position-dependent . No change in the trapped field was observed for about 25 d, which corresponded to a decay rate of less than 0.1 ppb h⁻¹. The obtained results suggest that the MgB₂ bulk magnet is a promising candidate for a magnetic pole in an NMR apparatus.

我们在磁场中测量了硅橡胶的¹ H 核磁共振 (NMR) 光谱，该磁场由紧凑的管状 MgB ₂超导体块状磁铁（外径 60 毫米、内径 40 毫米和高度 60 毫米）捕获，该磁铁被磁场磁化 -来自外加场0.4778 T 在 20 K 下的冷却磁化强度。共振频率20.314 MHz的最锐利¹ H NMR 谱对应于 0.4771 T 的场强，在中心下方 1 mm 处观察到MgB ₂管的孔。沿中心z轴的z -2 和 +2 mm之间的俘获场的均匀性在 100 ppm 之内，这是通过位置相关的. 在大约 25 d 内没有观察到捕获场的变化，这对应于小于 0.1 ppb h ^-1的衰减率。所得结果表明，MgB ₂块状磁体是NMR装置中磁极的有希望的候选者。