[12p-A501-1~16] 10.4 半導体スピントロニクス・超伝導・強相関

[12p-A501-14] GaAs/Al_0.3Ga_0.7As (110)超格子におけるスピン緩和

〇大野 裕三¹、岡本 亮吾¹、小畑 優真¹、大部 公暉¹、PASCUAL DOMINGUEZ JONATHAN JOHAN¹、揖場 聡²、齋藤 秀和² (1.筑波大、2.産総研)

キーワード：半導体超格子、スピン緩和、スピンレーザー

In semiconductor spin light emitting diodes or lasers, spin polarized electrons are injected into the active layer from ferromagnetic electrodes. In order to keep spin polarization during transport along the growth direction, we propose to use a superlattice (SL) on a (110) substrate. In this work, spin relaxation time of GaAs/Al_0.3Ga_0.7As (110) SL is studied by time- and polarization-resolved photoluminescence spectroscopy. As the tunnel coupling between quantum wells (QWs) is increased, the spin relaxation time at room temperature decreases. But even when the miniband width is as large as 25 meV, spin relaxation time is turned out to be 0.7 ns, about 7 times longer than that of bulk GaAs.