Magnetic head including stacked body with changing electrical resistance and magnetic recording device including same

A magnetic recording device, comprising:

• a magnetic head;
• and
• an electrical circuit,
• the magnetic head including
• a magnetic pole,
• a first shield, and
• a stacked body provided between the magnetic pole and the first shield,
• the stacked body including
• a first magnetic layer,
• a second magnetic layer,
• a first layer provided between the first magnetic layer and the second magnetic layer, the first layer including at least one selected from the group consisting of Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and
• a first nonmagnetic layer provided between the first magnetic layer and the first layer,
• a change rate of an electrical resistance of the stacked body with respect to a change of a current density flowing in the stacked body has
• a first value when the current density is in a first range,
• a second value when the current density is in a second range, and
• a third value when the current density is in a third range,
• the second range being between the first range and the third range, the second value being greater than the first value and greater than the third value,
• the electrical circuit supplying, to the stacked body, a current of a current density within the third range.