| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical modulation element having improved optical modulation degree using a spin injection magnetization reversal element. <P>SOLUTION: An optical modulation element 1 includes a spin injection magnetization reversal element structure in which a magnetization fixed layer 11 having perpendicular magnetic anisotropy, an intermediate layer 12 and a magnetization free layer 13 having the perpendicular magnetic anisotropy are stacked in this order, and changes a magnetization direction of the magnetization free layer 13 by supplying an electric current through a pair of electrodes 2 and 3 connected in a vertical direction. The magnetization free layer 13 is formed of a Gd-Fe alloy having a composition of 19-27 at% Gd and 73-81 at% Fe, and has a saturation magnetization of 50-250 emu/cc. The Gd-Fe alloy having a large magnetooptical effect contains a large amount of Fe, which can reduce an inversion current while holding stability of the magnetization direction and enables further improvement of the optical modulation degree by thickening a film of the magnetization free layer 13. <P>COPYRIGHT: (C)2012,JPO&INPIT |
