In-situ measurement of magnetic field gradient in a magnetic shield by a spin-exchange relaxation-free magnetometer*
Fang Jian-Chenga), Wang Taoa)†, Zhang Hongb), Li Yanga), Cai Hong-Weia)
       
Experimental result of the residual magnetic field along the z direction. The measurement of the magnetic field with low pumping power is inaccurate due to the light shift gradient and inhomogeneous polarization rate through the cell.