Patent ID: 7864473

Claim:
A magnetic recording system comprising: a magnetic recording medium including a substrate, a first ferromagnetic layer formed on said substrate, a nonmagnetic layer formed on said first ferromagnetic layer, and a second ferromagnetic layer formed on said nonmagnetic layer; a magnetic pole for applying a magnetic field H to invert a magnetizing direction of said first ferromagnetic layer; and means for applying a positive or a negative voltage V between a metallic probe and said magnetic recording medium, wherein a coercivity Hc 2 of said second ferromagnetic layer is larger than that Hc 1 of said first ferromagnetic layer; wherein a quantum well level is formed in said nonmagnetic layer formed between said first and second ferromagnetic layers; wherein said magnetic field H changes said magnetizing direction of said first ferromagnetic layer to a direction of an applied magnetic field; wherein applying said positive or negative voltage V changes an energy of said quantum well level between said first and second ferromagnetic layers, thereby inducing an exchange magnetic field H E ; and wherein said magnetic field H and said exchange magnetic field H E work together to invert said magnetizing direction of said second ferromagnetic layer.