Experimental demonstration of split side-gated resonant interband tunneling devices

We report a prototype side-gated asymmetric resonant interband tunneling device (RITD) fabricated with an AlSb∕InAs∕GaSb∕AlSb heterostructure for Rashba spin filter applications. This device features independent control gates along the sides of an RITD mesa structure that can be used to provide an electric field orthogonal to the resonant tunneling current. The distribution of lateral wave vectors for electrons approaching the RITD active layers obtains a nonzero average through the application of the orthogonal electric field, a requirement for Rashba spin filter operation. Measured current–voltage curves show a modulation of the tunneling current with a side gate bias, demonstrating lateral electric-field projection into the resonant tunneling mesa structure. The prototype device was fabricated to submicron dimensions utilizing a conformal and scalable processing scheme.