Mamr head with a multi-layered side gap for stable oscillation of the sto

A microwave-assisted magnetic recording (MAMR) head, comprising:

• a main pole configured to generate a magnetic field for recording data on a magnetic recording medium;
• a trailing shield positioned downstream from the main pole in a direction in which the magnetic recording medium advances;
• a spin torque oscillator (STO) configured to generate a high-frequency magnetic field, the STO being positioned between the main pole and the trailing shield;
• an electrically conductive non-magnetic body positioned on one or more sides of the main pole in a cross-track direction and/or a leading direction;
• and
• an insulating non-magnetic body positioned on one or more sides of the electrically conductive non-magnetic body in the cross-track direction and/or the leading direction,
• wherein one or more edge portions of one side of the STO and one or more edge portions of one side of the main pole are in direct contact with the electrically conductive non-magnetic body, and
• wherein all edge portions of one side of the STO are in direct contact with one of the main pole and the electrically conductive non-magnetic body.

A microwave-assisted magnetic recording (MAMR) head, comprising:

• a main pole comprising a magnetic body configured to generate a magnetic field for recording data on a magnetic recording medium;
• a trailing shield positioned downstream from the main pole in a direction in which the magnetic recording medium advances;
• a spin torque oscillator (STO) configured to generate a high-frequency magnetic field, the STO being positioned between the main pole and the trailing shield;
• a circuit configured to flow an electric current therethrough to the main pole, the STO, and the trailing shield;
• an electrically conductive non-magnetic body positioned on one or more sides of the main pole in a cross-track direction and/or a leading direction;
• and
• an insulating non-magnetic body positioned on one or more sides of the electrically conductive non-magnetic body in the cross-track direction and/or the leading direction,
• wherein all edge portions of one side of the STO are in direct contact with one of the main pole and the electrically conductive non-magnetic body, and
• wherein only one STO is positioned between the main pole and the trailing shield.