Patent ID: 8778701

Claim:
A method for producing a spin injection electrode, comprising: a first step of preparing a multi-layer graphene, and an iron oxide that contains Fe 3 O 4 and that is a ferromagnetic material contacting the graphene; and a second step of applying a voltage or a current between the graphene and the iron oxide, with an electric potential of the graphene being positive relative to that of the iron oxide, so as to: (a) convert a contact area of the graphene with the iron oxide into oxidized graphene by oxidation, and thus to form a barrier layer composed of the oxidized graphene between the graphene and the iron oxide; or (b) convert a contact area of the graphene with the iron oxide, and Fe 3 O 4 contained in a contact area of the iron oxide with the graphene, into oxidized graphene and Fe 2 O 3 respectively by oxidation, and thus to form a barrier layer composed of the oxidized graphene and Fe 2 O 3 between the graphene and the iron oxide, and thereby forming a spin injection electrode that comprises the graphene, the iron oxide, and the barrier layer located at an interface between the graphene and the iron oxide, and that allows spins to be injected into the graphene from the iron oxide via the barrier layer.