Magneto-resistive effect device, magnetic head gimbal assembly, magnetic recording/reproduction device, strain sensor, pressure sensor, blood pressure sensor, and structural health monitoring sensor

A magnetic head gimbal assembly, comprising:

• a magneto-resistive effect device, wherein,
• the magneto-resistive effect device includes:
• a stacked body stacked on a substrate, the stacked body including
• a first magnetic layer that includes one or more metals selected from the group consisting of iron, cobalt, and nickel,
• a second magnetic layer stacked on the first magnetic layer, having a composition that is different from the first magnetic layer, and
• a spacer layer disposed between the first magnetic layer and the second magnetic layer;
• a pair of first electrodes that feeds current to the stacked body;
• a strain introduction member that applies strain to the stacked body, that is provided near the stacked body, and by applying strain to the stacked body, biases magnetization directions of the first magnetic layer and the second magnetic layer in different directions;
• and
• a second electrode that applies a voltage to the strain introduction member, wherein
• the magnetization directions of the first magnetic layer and the second magnetic layer are changed by the application of an external magnetic field, and
• the external magnetic field is detected by a change in resistance between the first electrodes due to the change in the magnetization directions.

A magnetic recording/reproduction device, comprising:

• a magnetic head gimbal assembly that includes a magneto-resistive effect device;
• a magnetic head that includes the magneto-resistive effect device, mounted on the magnetic head gimbal assembly;
• and
• a magnetic recording medium that reproduces information using the magnetic head, wherein
• the magneto-resistive effect device includes
• a stacked body stacked on a substrate, the stacked body including:
• a first magnetic layer that includes one or more metals selected from the group consisting of iron, cobalt, and nickel,
• a second magnetic layer stacked on the first magnetic layer, having a composition that is different from the first magnetic layer, and
• a spacer layer disposed between the first magnetic layer and the second magnetic layer;
• a pair of first electrodes that feeds current to the stacked body;
• a strain introduction member that applies strain to the stacked body, that is provided near the stacked body, and by applying strain to the stacked body, biases magnetization directions of the first magnetic layer and the second magnetic layer in different directions;
• and
• a second electrode that applies a voltage to the strain introduction member, wherein
• the magnetization directions of the first magnetic layer and the second magnetic layer are changed by the application of an external magnetic field, and
• the external magnetic field is detected by a change in resistance between the first electrodes due to the change in the magnetization directions.