Magnetoresistive sensor having a magnetically stable free layer with a positive magnetostriction

A magnetoresistive sensor, comprising:

• a magnetic free-layer structure;
• a magnetic pinned-layer structure;
• and a nonmagnetic layer sandwiched between the free-layer structure and the pinned-layer structure;
• wherein
• the free-layer structure comprises a material having a positive magnetostriction and has a surface that is configured with an anisotropic surface texture;
• and wherein
• the free layer comprises Co72Fe8Be20.

A magnetoresistive sensor, comprising:

• a magnetic free-layer structure;
• a magnetic pinned-layer structure;
• and
• a nonmagnetic layer sandwiched between the free-layer structure and the pinned-layer structure;
• wherein
• the free-layer structure comprises a material having a positive magnetostriction and has a surface that is configured with an anisotropic surface texture;
• and
• wherein the anisotropic surface texture is in the form of ripples having an average depth of 0.5-5 nm.

A magnetoresistive sensor, comprising:

• a magnetic free layer;
• a magnetic pinned-layer structure;
• and
• a nonmagnetic layer sandwiched between the free layer and the pinned-layer structure;
• wherein
• the free layer comprises a Co—Fe—B alloy and has a surface that is configured with
• an anisotropic surface texture;
• and wherein
• the anisotropic surface texture is in the form of ripples having an average depth of 0.5-5 nm.

A magnetoresistive sensor,

• comprising:
• a magnetic free layer;
• a magnetic pinned-layer structure;
• and
• a nonmagnetic layer sandwiched between the free layer and the pinned-layer structure;
• wherein
• the free layer comprises a Co—Fe—B alloy and has a surface that is configured with an anisotropic surface texture;
• and
• wherein the free layer comprises Co72Fe8Be20.

A magnetoresistive sensor,

• comprising:
• a magnetic free layer,
• a magnetic pinned-layer structure;
• and
• a nonmagnetic layer sandwiched between the free layer and the pinned-layer structure;
• wherein
• the free layer comprises a Co—Fe—B alloy and has a surface that is configured with an anisotropic surface texture;
• and
• wherein the anisotropic surface texture is in the form of ripples having an average pitch of 10-200 nm.

A magnetic data storage system, comprising:

• a housing;
• a magnetic recording medium rotatably mounted within the housing;
• a slider;
• an actuator, connected with the slider for moving the slider relative to a surface of the magnetic recording medium;
• and
• a magnetoresistive sensor connected with the slider, the magnetoresistive sensor comprising:
• a magnetic free layer;
• a magnetic pinned-layer structure;
• and
• a nonmagnetic layer sandwiched between the free layer and the pinned-layer structure;
• wherein
• the free layer comprises a Co72Fe8Be20 alloy and has a surface that is configured with an anisotropic surface texture.