Orientation Characteristics in RF Magnetic Shielding Effects of BPSCCO Plates

As one of the basic areas of research for improvement of the electromagnetic environment by use of a bulk high-critical temperature superconductor, the present paper has examined a Bi-Pb-Sr-Ca-Cu-O (BPSCCO) plate with a slit, which displays orientation characteristics in the RF magnetic shielding. According to the results, the value of the RF magnetic shielding degree SD _HP, when orienting the slit of the BPSCCO plate perpendicular to the ground, increased in the frequency region of 1 MHz (20 dB) to 30 MHz (40 dB) , and then reminded approximately constant in the region of 30 MHz to 3 GHz (40 dB). The value of the RF magnetic shielding degree SD _HH when orienting the slit horizontally indicated an average value of 15 dB in the region of 1 MHz to 3 GHz. Namely, the difference in the RF magnetic shielding degree, SD _HP-SD _HH, as related to the direction of the slit represents orientation characteristics. Experimental results revealed several characteristics of the slit BPSCCO plate that include the dependencies of the orientation characteristics on the slit length, slit width, and slit number.