Ultrafast pulse field source utilizing optically induced magnetic transformation

1. A magnetic field transducer comprising:

a phase transition material exhibiting a change from an antiferromagnetic phase to a ferromagnetic phase when heated above a critical temperature;

a magnetic field source for applying a magnetic bias field to the phase transition material; and

a heat source for heating the phase transition material above the critical temperature;

wherein the phase transition material comprises a first section and a second section, and wherein the first section and the second section are separated to form a gap.

2. The magnetic field transducer of claim 1 , wherein the phase transition material is selected from a group consisting of: FeRh, and FeRhX, where X is one of Pd, Pt, Ir, Ru, Re or Os.

3. The magnetic field transducer of claim 1 , wherein the phase transition material comprises a rare earth/transition metal alloy.

4. A disc drive comprising:

a motor for supporting a storage medium;

the magnetic recording head of claim 1 ; and

an arm for positioning the magnetic recording head adjacent to the storage medium.

5. The magnetic field transducer of claim 1 , wherein the magnetic field source comprises:

a conductor for applying the magnetic bias field to the phase transition material.

6. The magnetic field transducer of claim 1 , wherein the heat source comprises:

a source of electromagnetic radiation; and

a waveguide for directing electromagnetic radiation from the source onto the phase transition material.

7. A magnetic recording head including a write pole comprising the transducer of claim 1 .

8. A method of producing a magnetic pulse, the method comprising:

providing a phase transition material, wherein the phase transition material comprises a first section and a second section, and wherein the first section and the second section are separated to form a gap;

applying a magnetic bias field to the phase transition material; and

heating the phase transition material to cause the phase transition material to change from an antiferromagnetic phase to a ferromagnetic phase, thereby producing a magnetic pulse.

9. The method of claim 8 , wherein the step of heating the phase transition material comprises:

directing an electromagnetic wave onto the phase transition material.

10. The method of claim 8 , wherein the phase transition material comprises FeRh or FeRhX, wherein X is selected from the group of Pd, Pt, Ir, Ru, Re or Os.

11. The method of claim 8 , wherein the phase transition material comprises a rare earth/transition metal alloy.

12. The method of claim 8 , wherein the step of applying a magnetic bias field to the phase transition material comprises:

passing an electric current through a conductor to apply the magnetic bias field to the phase transition material.

13. A recording head for use with a data in a storage medium, the recording head comprising:

a write pole including a phase transition material;

a return pole magnetically coupled to the write pole;

a transmission line positioned adjacent to the phase transition material, wherein current flowing in the transmission line applies a magnetic bias field to the phase transition material; and

a heat source for heating the phase transition material;

wherein the phase transition material comprises FeRh or FeRhX, wherein X is selected from the group of Pd, Pt, Jr. Ru, Re or Os.

14. The recording head of claim 13 , wherein the write pole includes a tapered portion connected to the phase transition material portion.

15. A method of recording data in a storage medium, the method comprising:

placing a phase transition material adjacent to a surface of the storage medium, wherein the phase transition material comprises a first section and a second section, and wherein the first section and the second section are separated to form a gap;

applying a magnetic bias field to the phase transition material;

heating the phase transition material to cause the phase transition material to change from an antiferromagnetic phase to a ferromagnetic phase, thereby producing a magnetic pulse; and

using the magnetic pulse to affect the magnetization of the storage medium.

16. The method of claim 15 , wherein the phase transition material comprises FeRh or FeRhX, wherein X is selected from the group of Pd, Pt, Ir, Ru, Re or Os.

17. The method of claim 15 , wherein the phase transition material comprises a rare earth/transition metal alloy.

18. The method of claim 15 , wherein the step of heating the phase transition material comprises:

directing an electromagnetic wave onto the phase transition material.

19. The method of claim 15 , wherein the step of applying a magnetic bias field to the phase transition material comprises:

passing an electric current through a conductor to apply the magnetic bias field to the phase transition material.

20. A recording head for use with a data in a storage medium, the recording head comprising:

a write pole including a phase transition material, wherein the phase transition material is divided into two sections;

a return pole magnetically coupled to the write pole;

a magnetic field source for applying a magnetic bias field to the phase transition material; and

a heat source for heating the phase transition material to cause the phase transition material to change from an antiferromagnetic phase to a ferromagnetic phase, thereby producing a magnetic pulse that can affect the magnetization of the storage medium, wherein the magnetic pulse is produced between the two sections.

21. The recording head of claim 20 , wherein heat source comprises:

a source of an electromagnetic radiation; and

a waveguide for directing the electromagnetic radiation onto the phase transition material.

22. The recording head of claim 20 , wherein the phase transition material comprises FeRh or FeRhX, wherein X is selected from the group of Pd, Pt, Ir, Ru, Re or Os.

23. The recording head of claim 20 , wherein the phase transition material comprises a rare earth/transition metal alloy.