A heat assisted magnetic recording disk drive comprises a magnetic recording media with a heat sink layer including at least a material being defined by the general structure M.sub.n+1AX.sub.n, wherein M is a transition metal, A is an A-group element, X is C or N or a mixture of C and N, and n is a positive integer, or a material defined by the general structure M.sub.n+1AX.sub.n, wherein M is a transition metal, X is one or both of C and N, and n is a positive integer, or a mixture of the materials being defined by the general structure M.sub.n+1AX.sub.n and the material defined by the general structure M.sub.n+1X.sub.n, wherein the crystal structure of the materials is hexagonal with repeated M-X-M (quasi 2D) atomic layers. The atomic layers are stacked along the {right arrow over (c)}-axis that is oriented substantially parallel to the surface normal of the heat sink layer.

A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having an L1.sub.0 structure. The substrate, the underlayer, and the magnetic layer are stacked in the recited order. The underlayer includes a first underlayer. The first underlayer includes magnesium oxide and one or more compounds selected from the group consisting of vanadium oxide, zinc oxide, tin oxide, vanadium nitride, and vanadium carbide, and a total content of the one or more compounds is in a range of 45 mol % to 70 mol %.

A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having an L1.sub.0 structure. The substrate, the underlayer, and the magnetic layer are stacked in the recited order. The underlayer includes a first underlayer. The first underlayer includes magnesium oxide and one or more compounds selected from the group consisting of vanadium oxide, zinc oxide, tin oxide, vanadium nitride, and vanadium carbide, and a total content of the one or more compounds is in a range of 45 mol % to 70 mol %.

A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having an L1.sub.0 structure, wherein the underlayer includes, from the substrate side, a bcc underlayer including a substance having a bcc structure, a first oxide layer that is in contact with the bcc underlayer, and a second oxide layer that is in contact with the magnetic layer. The bcc underlayer, the first oxide layer, and the second oxide layer are stacked in the recited order. The first oxide layer and the second oxide layer include magnesium oxide, and the second oxide layer further includes one or more compounds selected from the group consisting of vanadium oxide, vanadium nitride, and vanadium carbide.

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium. The HAMR medium includes a substrate, a heat sink layer on the substrate, and a plurality of magnetic recording layers on the heat sink layer. The plurality of magnetic recording layers includes a first magnetic layer and a second magnetic layer disposed on the first magnetic layer. The second magnetic layer includes FePtAgCuX, wherein X is a segregant comprising BN. The HAMR medium can use BN-based segregants to improve a thermal gradient of the HAMR medium for better areal density capability (ADC) and enable the use of a MgO underlayer with reduced thickness.

A magnetic disk used in a hard disk drive device includes a substrate; a magnetic recording layer; and a heat insulating layer provided between the substrate and the magnetic recording layer. Even though a substrate has low heat resistance, as a result of providing the heat insulating layer, the substrate can be used as a substrate for a magnetic disk that can withstand heat treatment (high-temperature annealing).

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

Various apparatuses, systems, methods, and media are disclosed for heat-assisted magnetic recording (HAMR) that, in some examples, provide a HAMR medium with two soft underlayers (SULs) on opposing sides of a single heatsink layer. For example, a magnetic recording medium is provided that includes a lower SUL on a substrate. The lower SUL is configured and positioned within the medium to provide a first return path for magnetic flux from a magnetic recording head during a write operation. The medium also includes a heatsink layer on the lower SUL and an upper SUL on the heatsink layer. The upper SUL is configured and positioned within the medium to provide a second return path for magnetic flux from the magnetic recording head. A magnetic recording layer is provided on the upper SUL to store information during the write operation. Additional layers or films may be provided as well.

A stack includes a substrate and a magnetic recording layer. Disposed between the substrate and magnetic recording layer is an MgOTi(ON) layer.