Monday, December 21, 2009

US Patent 7633715 - Magnetic recording head with CNT field emitter heating

Heat-assisted magnetic recording is a technology for providing high density data storage using phenomena in which thermal energy assists in switching magnetic domains. This patent from Pioneer Corporation teaches a variation of this type of recording system in which the thermal energy source uses carbon nanotubes which form an electron beam having minimum fluctuation. Claim 1 reads:

1. A magnetic head for use in a magnetic recording apparatus of magnetically recording information in a state of heating and elevating the temperature of a recording portion of a recording medium by emitting electrons to the recording medium, the magnetic head comprising:

a recording magnetic pole opposed to the recording medium and having a recording magnetic pole surface for supplying a magnetic flux to the recording medium; and

an electron emission source formed to the recording magnetic pole, wherein the electron emission source includes: a concave portion having an opening having a width and formed to the recording magnetic pole having length and open to the recording magnetic pole surface;

a bundle of a plurality of carbon nanotubes having length extending from the bottom to the opening of the concave portion, wherein the length of the carbon nanotubes is less than the length of the recording magnetic pole, and wherein said width of said opening is less than a recording track width.