Magnetic recording medium and magnetic storage apparatus

1. A magnetic recording medium comprising:

a substrate;

a first underlayer consisting of one of a Mo layer, a Mo—W layer, a Mo—Cu layer, a Mo—Ni layer, a Mo—Fe layer, a Mo—Re layer, and a Mo—C layer;

a second underlayer; and

a magnetic layer including an alloy having a L1 0 type crystal structure with a (001) orientation,

wherein the substrate, the first underlayer, the second underlayer, and the magnetic layer are stacked in this order,

wherein the first underlayer is a crystalline layer that includes Mo as a main component,

wherein the second underlayer is a crystalline layer that includes a material containing Mo as a main component and that includes an oxide, a content of the oxide in the second underlayer being in a range of from 3.3 mol % to 23.3 mol %, and

wherein the oxide is an oxide of one or more kinds of elements selected from a group consisting of Cr, Mo, Nb, Ta, V, and W.

2. The magnetic recording medium according to claim 1 , wherein the oxide is an oxide of Mo.

3. The magnetic recording medium according to claim 1 , wherein the second underlayer has a non-granular structure.

4. The magnetic recording medium according to claim 1 , further comprising:

a barrier layer between the second underlayer and the magnetic layer,

wherein the barrier layer includes one or more compounds selected from a group consisting of MgO, TiO, NiO, TiN, TaN, HfN, NbN, ZrC, HfC, TaC, NbC, and TiC, and has a NaCl type structure.

5. The magnetic recording medium according to claim 1 , further comprising:

an orientation control layer between the substrate and the first underlayer,

wherein the orientation control layer is a Cr layer having a BCC structure, an alloy layer containing Cr as a main component and having a BCC structure, or an alloy layer having a B2 structure.

6. A magnetic storage apparatus comprising the magnetic recording medium according to claim 1 .