The weak magnetic field sensor 1, in which material of {HEAD ~ the magnetic layer} is selected from a group consisting of amorphous metal, {TAIL ~ Permalloy} and Supermalloy 
The weak magnetic field sensor 1 , in which material of { HEAD ~ the magnetic layer } is selected from a group consisting of amorphous metal , { TAIL ~ Permalloy } and Supermalloy
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH