Heat-assisted magnetic recording head
View Patent ↗A heat-assisted magnetic recording head mounted on an end of a slider having an Air Bearing Surface (“ABS”) for recording data on a recording medium. The heat-assisted magnetic recording head includes a magnetic path forming unit that generates a magnetic field for recording the data, a light source that emits light heating a local region of the recording medium, a waveguide located on a side of the magnet path forming unit to transmit the light emitted from the light source, an optical path conversion unit that changes a direction of the light transmitted from the waveguide to the local region of the recording medium, and a nano-aperture that generates an enhanced near-field effect by converting an energy distribution of the light transmitted via the optical path conversion unit.
1. A heat-assisted magnetic recording head mounted on an end of a slider having an Air Bearing Surface for recording data on a recording medium, the heat-assisted magnetic recording head comprising:
a magnetic path forming unit that generates a magnetic field for recording the data;
a light source that emits light to heat a local region of the recording medium;
a waveguide located on a side of the magnetic path forming unit, the waveguide transmits the light emitted from the light source;
an optical path conversion unit that changes a direction of the light transmitted from the waveguide to the local region of the recording medium; and
a nano-aperture configured to generate an enhanced near-field effect by converting an energy distribution of the light transmitted via the optical path conversion unit.
2. The heat-assisted magnetic recording head of claim 1 , wherein the optical path conversion unit is a mirror formed on an end of the waveguide and inclined so as to direct light traveling along the waveguide towards the nano-aperture.
3. The heat-assisted magnetic recording head of claim 1 , wherein the optical path conversion unit is a grating pattern formed on a surface of the waveguide so as to direct light traveling along the waveguide towards the nano-aperture.
4. The heat-assisted magnetic recording head of claim 3 , wherein spacing of the grating pattern is reduced toward a central portion of the grating pattern.
5. The heat-assisted magnetic recording head of claim 1 , wherein the magnetic path forming unit comprises:
a coil that provides a magnetic field source;
a main pole comprising a first end portion that faces the recording medium and is located on a plane of the air bearing surface;
a sub-yoke disposed on a side surface of the main pole and comprising a second end portion that faces the recording medium, wherein the first and second end portions are stepped to focus the electric field on the first end portion; and
a return yoke forming the magnetic path of the magnetic field together with the main pole and comprising a one end of the return yoke spaced apart from the main pole and another end of the return yoke connected to the main pole.
6. The heat-assisted magnetic recording head of claim 5 , wherein at least a part of the waveguide, the optical path conversion unit, and the nano-aperture are arranged in a space between the first and second end portions.
7. The heat-assisted magnetic recording head of claim 5 , wherein a saturation magnetization value of the main pole is greater than that of the sub-yoke.
8. The heat-assisted magnetic recording head of claim 1 , wherein the waveguide comprises:
a first clad layer;
a second clad layer; and
a core layer disposed between the first and second clad layers and having a refractive index greater than a refractive index of the first clad layer and greater than a refractive index of the second clad layer.
9. The heat-assisted magnetic recording head of claim 8 , wherein the waveguide is a graded index type waveguide having a refractive index that is maximum at a central portion and is gradually reduced toward the first and second clad layers.
10. The heat-assisted magnetic recording head of claim 1 , further comprising:
a first shield;
a second shield spaced apart from the first shield; and
a reproduction member disposed between the first and second shields,
wherein surfaces of the first shield, the second shield, and the reproduction member opposite to the recording medium are located on a plane of the air bearing surface.
11. The heat-assisted magnetic recording head of claim 10 , wherein the waveguide is formed of polymer.
12. The heat-assisted magnetic recording head of claim 1 , wherein the light source is butt-coupled to the waveguide.
13. The heat-assisted magnetic recording head of claim 1 , further comprising a prism coupler that couples the light source to the waveguide.
14. A heat-assisted magnetic recording head mounted on an end of a slider having an Air Bearing Surface for recording data on a recording medium, the heat-assisted magnetic recording head comprising:
a magnetic path forming unit that generates a magnetic field for recording the data;
a light source that emits light to heat a local region of the recording medium;
a waveguide located on a side of the magnetic path forming unit, the waveguide transmits the light emitted from the light source; and
means for generating an enhanced near-field effect by converting an energy distribution of the light source.
15. A heat-assisted magnetic recording head for mounting on an end of a slider having an Air Bearing Surface for recording data on a recording medium, the heat-assisted magnetic recording head comprising:
a magnetic path forming unit that generates a magnetic field for recording the data and comprising a main pole and a sub-yoke;
a light source that emits light to heat a local region of the recording medium;
a waveguide that transmits the light emitted from the light source; and
a nano-aperture optically coupled to the waveguide; and
wherein the waveguide is located in a space between the sub-yoke and the main pole.