1:30 PM - 3:30 PM
▲ [9p-PB1-79] Nearly pure circular polarization electroluminescence from spin-LED with significantly reduced current densities
Keywords:Spin-photonics, Circularly polarized light, Tunneling barrier
Electroluminescence (EL) with nearly pure circular polarization (CP) at room temperature has been demonstrated by a lateral-type spin-LEDs consisting of AlGaAs/GaAs double-heterostructures and the crystalline AlOx (x-AlOx) tunneling barrier. In this LT-spin-LED, relatively high current density of J > 100 A/cm2 was required to achieve the circular polarization of P ~ 0.95. Operation with J > 100 A/cm2, however, often resulted in irreversible breakdown and short-lived spin-LED. In order to suppress this breakdown, we have studied fabrication of LT-spin-LED devices incorporating x-AlOx/AlAs hybrid tunneling barriers. With AlAs layers that are inserted between the x-AlOx layer and a top n-GaAs layer of LT-spin-LED, we aim at reinforcing electrical robustness of x-AlOx tunneling barriers that are formed by oxidation of Al epilayers at RT. Consequently, we achieved EL with nearly pure CP with significantly reduced current densities and the yield of device fabrication is significantly improved.