Differential detection read sensor, thin film head for perpendicular magnetic recording and perpendicular magnetic recording apparatus

A reproducing sensor comprising:

• a multi-layer construction having;
• a first MR element comprising a first ferromagnetic (pin), a second ferromagnetic layer (free) and a non-magnetic insulting layer formed between the first ferromagnetic layer and the second ferromagnetic layer,
• a second MR element comprising a third ferromagnetic layer (free), a fourth ferromagnetic layer (pin) and non-magnetic insulting layer formed between the first ferromagnetic and the second ferromagnetic layer, and
• a non-magnetic conductive layer formed between the second ferromagnetic layer (free) and the third ferromagnetic layer (free),
• wherein a resistance of the first MR element and the second MR element is changed reversely from the magnetic field in the same direction,
• magnetization directions of the first ferromagnetic layer and the fourth ferromagnetic layer are arranged in antiparallel with each other,
• a pair of electrodes for flowing an electric current in the direction perpendicular to the film surface of the multi-layer construction, and
• a pair of shield inserting the multi-layer construction,
• wherein the first MR element and the second MR element are electrically connected in series through the non-magnetic conductive layer by passing current between the pair of electrodes, and are patterned together with almost the same width.