Magnetic storage apparatus

A magnetic storage apparatus including a perpendicular magnetic recording medium, and a magnetic head having a recording unit and a read element, in which

• the recording unit of the magnetic head has a main pole, an auxiliary pole, and a magnetic shield disposed at least on the trailing side of the main pole, wherein the magnetic shield disposed at least on the trailing side of the main pole is not magnetically coupled to the main pole,
• the perpendicular magnetic recording medium has a first recording layer having a granular structure comprising grain boundaries containing an oxide and columnar grains comprising a CoCrPt alloy, a second recording layer formed over the first recording layer, and a third recording layer formed over the second recording layer, the second recording layer and the third recording layer comprise Co as a main ingredient, contain Cr and do not contain an oxide, and the Cr concentration in the second recording layer is lower than the Cr concentration in the third recording layer,
• wherein t2/(t2+t3) is 0.1 or more and 0.4 or less in which t2 is a thickness of the second recording layer and t3 is a thickness of the third recording layer.

A magnetic storage apparatus including a perpendicular magnetic recording medium, and a magnetic head having a recording unit and a read element, in which

• the recording unit of the magnetic head has a main pole, an auxiliary pole, a magnetic shield disposed at least on the trailing side of the main pole, and an auxiliary magnetic shield disposed between the main pole and a read shield, the read shield being positioned between the read element and the main pole
• the perpendicular magnetic recording medium has a first recording layer having a granular structure comprising grain boundaries containing an oxide and columnar grains comprising a CoCrPt alloy, a second recording layer formed over the first recording layer, and a third recording layer formed over the second recording layer, wherein the second recording layer and the third recording layer comprise Co as a main ingredient, contain Cr and do not contain an oxide, and the Cr concentration in the second recording layer is lower than the Cr concentration in the third recording layer
• wherein t2/(t2+t3) is 0.1 or more and 0.4 or less in which t2 is a thickness of the second recording layer and t3 is a thickness of the third recording layer.