Recording layer, information recording medium, and target

An information recording medium comprising:

• a plurality of recording layers, wherein at least one of the plurality of recording layers comprises an oxide of Mn, and Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein at least one of the recording layers further includes an oxide of Mg.

A recording layer comprising:

• an oxide of Mn, wherein Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein the recording layer further includes an oxide of Mg.

A target for use in manufacturing an information recording medium, the target comprising:

• an oxide of Mn, wherein the oxide of Mn is partially or fully present as an oxide of Mn with a valence of less than +4,
• wherein the target further includes Mg or an oxide of Mg.

An information recording medium comprising:

• a recording layer comprising an oxide of Mn, wherein Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein the recording layer further comprises an oxide of at least one metal element selected from the group consisting of Mg, Mo, Si, and Te.

An information recording medium comprising:

• a recording layer comprising an oxide of Mn, wherein Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein the recording layer further comprises Ru.

An information recording medium comprising:

• a recording layer comprising an oxide of Mn, wherein Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein the information recording medium further comprising a first dielectric layer provided on a first surface of the recording layer and a second dielectric layer provided on a second surface of the recording layer, wherein the first and second dielectric layers comprise an oxide of In and an oxide of Zr.

An information recording medium comprising:

• a recording layer comprising an oxide of Mn, wherein Mn atoms in the oxide of Mn are partially or fully present as Mn with a valence of +4,
• wherein the information recording medium further comprising a first dielectric layer provided on a light-receiving surface of the recording layer;
• and a second dielectric layer provided on another surface opposite to the light-receiving surface, wherein the first dielectric layer comprises an oxide of Zr, and the second dielectric layer comprises an oxide of In and an oxide of Zr.

A target for use in manufacturing an information recording medium, the target comprising:

• an oxide of Mn, wherein the oxide of Mn is partially or fully present as an oxide of Mn with a valence of less than +4,
• wherein the target further includes a metal or an oxide of the metal, and wherein the metal is at least one selected from the group consisting of Sn, Zn, Bi, Ge, Co, W, Cu, and Al.