Low-<em> T</em><sub>c</sub> direct current superconducting quantum interference device magnetometer-based 36-channel magnetocardiography system in a magnetically shielded room

Low- T_c direct current superconducting quantum interference device magnetometer-based 36-channel magnetocardiography system in a magnetically shielded room

Qiu Yang^a),^b),^c), Li Hua^a),^b),^c), Zhang Shu-Lin^a),^b), Wang Yong-Liang^a),^b), Kong Xiang-Yan†^a),^b), Zhang Chao-Xiang^a),^b), Zhang Yong-Sheng^a),^b), Xu Xiao-Feng^a),^b), Yang Kang^a),^b),^c), Xie Xiao-Ming^a),^b)

Statistical characterizations of the voltage-biased SQUID magnetometers: (a) I _swing; (b) SQUID noise, (c) the noise measurements of a typical noise spectrum measurement of the SQUID magnetometers, whose ∂B / ∂ Φ is measured to be 0.55 nT/ Φ ₀.