Baseline optimization of SQUID gradiometer for magnetocardiography*
Li Huaa),b),c), Zhang Shu-Lina),b)†, Qiu Yanga),b),c), Zhang Yong-Shenga),b), Zhang Chao-Xianga),b), Kong Xiang-Yana),b)‡, Xie Xiao-Minga),b)
       
(a) Measured signal and noise (b) SNR.