{HEAD ~ The trilayer sensor} is biased by a back biasing magnet positioned at {TAIL ~ the back end} of the stack 
{ HEAD ~ The trilayer sensor } is biased by a back biasing magnet positioned at { TAIL ~ the back end } of the stack
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH