Temporal Stabilization of Magnetic Flux Focused by Superconducting Magnetic Lens

Optimized performance of an all-REBaCuO hybrid trapped field magnet lens (HTFML) with liquid nitrogen cooling

“…Ring-shaped bulk superconductors, that can produce uniform and high magnetic fields in their central bore, are a powerful candidate for compact cryogen-free nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) systems [5][6][7]. In addition, as a magnetic field concentrator, a magnetic lens made of bulk REBaCuO has been also developed [8][9][10][11][12][13][14]. When an external magnetic field is applied to the bulk magnetic lens in the superconducting state during the zero-field cooled magnetization (ZFCM) process, a shielding current is induced so as to prevent magnetic flux penetration into the bulk due to the so-called 'diamagnetic shielding effect'.…”

Experimental realization of a hybrid trapped field magnet lens using a GdBaCuO magnetic lens and MgB2 bulk cylinder

“…On the other hand, a 'magnetic lens' using cone-shaped superconducting bulks has been investigated, in which a magnetic field is concentrated in the bore of the lens using the 'diamagnetic shielding effect' of superconducting materials and the available magnetic field in the lens is higher than the applied field generated by an external magnetizing coil [12][13][14][15][16][17][18]. For example, a concentrated field of B c =12.42 T has been achieved at 20 K for a background field of B app =8 T using a bulk GdBaCuO magnetic lens [12].…”