Electroluminescence And Spin-Polarized Hole Injection In InAs∕GaAs Quantum Dot Heterostructures

Abstract

Abstract. We demonstrate the feasibility to obtain electroluminescence (EL), up to room temperature, from self-assembled quantum dots included in a Schottky diode. Moreover, using a ferromagnet as the contact layer, sizable circular polarization of the emission in the presence of an external magnetic field (B) is obtained. A resonant behavior of the degree of circular polarization as a function of applied voltage, for a given B, is observed. We explain our findings using a model including tunneling through the metal-semiconductor interface, transport in the near surface region of the heterostructure and out-ofequilibrium statistics of the injected carriers.