Trailing edge recording magnetic head with reversed double bias coil and deflection pole for perpendicular recording with a non-perpendicular write field

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron, the return pole tip residing between the write pole tip and the leading end;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• and
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end;
• and
• wherein the write pole tip has a medium-facing area that is less than about thirty thousand square nanometers.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end;
• and
• further comprising a magnetoresistive sensor disposed less than one-half micron from the return pole tip.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading ends a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end;
• and
• wherein a distance between the write pole tip and the deflection pole tip is approximately equal to a spacing between the write pole tip and the soft magnetic underlayer of the medium.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip and being spaced apart from the write pole tip by at least one micron;
• and
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip;
• and
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap;
• wherein the nonferromagnetic gap expands at a throat height, the throat height being measured from the medium-facing surface and being less than one-half micron.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip;
• and
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap;
• wherein the write pole tip has a trailing corner adjoining the nonferromagnetic gap, the return pole tip has a leading corner adjoining the nonferromagnetic gap, and the trailing corner is made of higher magnetic saturation material than that of the leading corner.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip;
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap;
• and
• a magnetoresistive sensor disposed less than one-half micron from the return pole tip.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip;
• and
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap;
• wherein a distance between the write pole tip and the deflection pole tip is approximately equal to a spacing between the write pole tip and the soft magnetic underlayer of the medium.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• first and second electrically conductive coils disposed in the body to carry current in substantially opposite directions to induce a magnetic field between the coils that is stronger than the field induced outside the coils, the second coil disposed closer than the first cool to the trailing end;
• a ferromagnetic write pole layer disposed between the coils and terminating in a write pole tip that is disposed adjacent to the medium-facing surface;
• a ferromagnetic return pole structure that is magnetically coupled to the write pole layer in a region encircled by the first coil, the return pole structure terminating adjacent to the medium-facing surface in a return pole tip having an area at least two orders of magnitude greater than that of the write pole tip;
• and
• a ferromagnetic deflection pole structure that is magnetically coupled to the write pole layer in a region encircled by the second coil, the deflection pole structure terminating adjacent to the medium-facing surface in a deflection pole tip that is separated from the write pole tip by a submicron nonferromagnetic gap;
• wherein the write pole tip has a medium-facing area that is less than about thirty thousand square nanometers.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end;
• and
• wherein the nonmagnetic gap expands at a throat height, the throat height being measured from the medium-facing surface and being less than one-half micron.

A magnetic head for writing information on a relatively-moving medium including a media layer and a soft magnetic underlayer, the head comprising:

• a body having a leading end, a trailing end and a medium-facing surface;
• a first ferromagnetic loop terminating in a write pole tip and a return pole tip that are disposed adjacent to the medium-facing surface and separated from each other by more than one micron;
• a second magnetic loop terminating in the write pole tip and a deflection pole tip that is disposed adjacent to the medium-facing surface between the write pole tip and the trailing end, the write pole tip and the deflection pole tip magnetically coupled to each other across a nanoscale nonmagnetic gap;
• an electrically conductive coil section that is at least partly encircled by one of the magnetic loops to induce a magnetic flux to traverse the write pole tip;
• wherein the magnetic flux traversing the write pole tip has a maximum strength in the media layer at a distance from the write pole tip that is less than a spacing between the write pole tip and the trailing end;
• and
• wherein the write pole tip has a trailing corner adjoining the nonmagnetic gap, the return pole tip has a leading corner adjoining the nonmagnetic gap, and the trailing corner is made of higher magnetic saturation material than that of the leading corner.