Magnetoresistive element and magnetic memory

A magnetoresistive element comprising:

• a first magnetic layer;
• an MgFeO layer;
• and
• a second magnetic layer stacked in a first direction, the MgFeO layer disposed between the first and second magnetic layers;
• wherein
• Fe of the MgFeO layer is included at least in a central portion of the MgFeO layer in the first direction, and
• the MgFeO layer contains boron.

A magnetoresistive element comprising:

• a first magnetic layer having a variable magnetization direction;
• a second magnetic layer having an invariable magnetization direction;
• and
• a tunnel barrier layer provided between the first magnetic layer and the second magnetic layer and including an MgFeO layer, wherein
• Fe of the MgFeO layer is included at least in a central portion of the MgFeO layer in a thickness direction,
• at least one of a concentration of Fe in a region between the first magnetic layer and the MgFeO layer and a concentration of Fe in a region between the second magnetic layer and the MgFeO layer is higher than a concentration of Fe at the central portion of the MgFeO layer, and
• the MgFeO layer contains at least one element selected from a group consisting of Ti, V, Mn, and Cu.

A magnetoresistive element comprising:

• a first magnetic layer having a variable magnetization direction;
• a second magnetic layer having an invariable magnetization direction;
• and
• a tunnel barrier layer provided between the first magnetic layer and the second magnetic layer and including an MgFeO layer, wherein
• Fe of the MgFeO layer is included at least in a central portion of the MgFeO layer in a thickness direction,
• at least one of a concentration of Fe in a region between the first magnetic layer and the MgFeO layer and a concentration of Fe in a region between the second magnetic layer and the MgFeO layer is higher than a concentration of Fe at the central portion of the MgFeO layer, and
• the MgFeO layer contains boron.