SPIN-INJECTION MAGNETIZATION-REVERSAL MAGNETO-RESISTANCE ELEMENT USING QUANTUM SIZE EFFECT

摘要

PROBLEM TO BE SOLVED: To increase the efficiency of spin-injection magnetization reversal and reduce power required for reversal of magnetization accompanying this.;SOLUTION: This magneto-resistance element has a lamination structure comprising a p⁺-GaAs layer 31, p-GaAs bottom electrode layer 33, (Ga, Mn)As fixed layer 35, AlAs second barrier layer 37, (In, Ga, Mn)As magnetization-reversal layer 39, AlAs first barrier layer 41, and transparent electrode layer 45. The magnetization direction of the (Ga, Mn)As fixed layer 35 is fixed, while the (In, Ga, Mn)As quantum well layer (magnetization reversal layer) 39 is a free layer. When circularly polarized light is not irradiated, the magnetization direction of the magnetization reversal layer 39 is kept in the former state and a resistance in the lamination direction becomes low. When right circularly polarized light is irradiated in the lamination direction, the direction of magnetization of the magnetization reversal layer changes, making the magnetization directions of the fixed layer 35 and the magnetization reversal layer 39 different by irradiation of the circularly polarized light (non-parallel magnetization). Even if the irradiation of the circularly polarized light is stopped, the resistance is still low to maintain the non-parallel magnetized state and this state is memorized non-volatilely. When circularly polarized light is irradiated in the lamination direction again, the fixed layer 35 and the magnetization reversal layer 39 become magnetized in the same direction and the resistance becomes high.;COPYRIGHT: (C)2005,JPO&NCIPI