Discrete track media (DTM) design and fabrication for heat assisted magnetic recording (HAMR)
View Patent ↗An apparatus includes a recording media including a substrate, a plurality of tracks of magnetic material on the substrate, and a non-magnetic material between the tracks; a recording head having an air bearing surface positioned adjacent to the recording media, and including a magnetic pole, an optical transducer, and a near-field transducer, wherein the near-field transducer directs electromagnetic radiation onto tracks to heat portions of the tracks and a magnetic field from the magnetic pole is used to create magnetic transitions in the heated portions of the tracks; and a plasmonic material positioned adjacent to the magnetic material to increase coupling between the electromagnetic radiation and the magnetic material.
1. An apparatus comprising:
a discrete track recording media including a substrate, a plurality of concentric tracks of continuous magnetic material on the substrate, and a non-magnetic material between the tracks;
a recording head having an air bearing surface positioned adjacent to the recording media, and including a magnetic pole, an optical transducer, and a near-field transducer, wherein the near-field transducer directs electromagnetic radiation onto tracks to heat portions of the tracks and a magnetic field from the magnetic pole is used to create magnetic transitions in the heated portions of the tracks; and
a continuous layer of plasmonic material positioned in the recording media and adjacent to the magnetic material to increase coupling between the electromagnetic radiation and the magnetic material.
2. The apparatus of claim 1 , wherein the near-field transducer directs the electromagnetic radiation to a spot having a diameter less than a width of the tracks.
3. The apparatus of claim 1 , wherein the plasmonic material is positioned on top of the magnetic material.
4. The apparatus of claim 1 , wherein the plasmonic material is positioned under the magnetic material.
5. The apparatus of claim 1 , wherein the plasmonic material is positioned both on top of and under the magnetic material.
6. The apparatus of claim 1 , wherein the plasmonic material is positioned both on top of the magnetic material, and on opposite sides of the magnetic material.
7. The apparatus of claim 1 , wherein the plasmonic material is positioned both under the magnetic material, and on opposite sides of the magnetic material.
8. The apparatus of claim 1 , wherein the recording media further comprises a heat sink layer between the substrate and the magnetic material.
9. The apparatus of claim 1 , wherein the magnetic material comprises:
a multilayer stack of at least two different types of magnetic material.
10. The apparatus of claim 9 , wherein the plasmonic material is positioned on top of the multilayer stack.
11. The apparatus of claim 9 , wherein the plasmonic material is positioned under the multilayer stack.
12. The apparatus of claim 9 , wherein the plasmonic material is positioned both on top of and under the multilayer stack.
13. The apparatus of claim 9 , wherein the plasmonic material is positioned both on top of the magnetic material, and on opposite sides of the multilayer stack.
14. The apparatus of claim 9 , wherein the plasmonic material is positioned both under the magnetic material, and on opposite sides of the multilayer stack.
15. The apparatus of claim 9 , wherein the multilayer stack comprises:
a first layer of FePtCu or FePtBCu; and
a second layer of FePtCu or FePtBCu.
16. The apparatus of claim 1 , wherein the magnetic material comprises:
one or more of CoCrPt granular media with or without an exchange coupling composite structure, a Co/Pt granular multilayer, and an FePt based L1 0 alloy.
17. The apparatus of claim 1 , wherein the plasmonic material comprises:
one or more of Au, Ag, Cu and alloys of Au, Ag or Cu.
18. The apparatus of claim 1 , wherein the non-magnetic material comprises:
a nitride material.
19. The apparatus of claim 1 , wherein the non-magnetic material comprises:
one or more of AlO, TiO, TaO, MgO, SiN, TiN, or AlN.
20. An apparatus comprising:
a recording media including a substrate, a plurality of concentric tracks of continuous magnetic material on the substrate, and a non-magnetic material between the tracks;
a recording head having an air bearing surface positioned adjacent to the recording media, and including a magnetic pole, an optical transducer, and a near-field transducer, wherein the near-field transducer directs electromagnetic radiation onto tracks to heat portions of the tracks and a magnetic field from the magnetic pole is used to create magnetic transitions in the heated portions of the tracks; and
a continuous layer of plasmonic material positioned in the recording media and adjacent to the magnetic material to increase coupling between the electromagnetic radiation and the magnetic material, wherein the tracks have a width of about 50 nm and are separated by about 25 nm.