Robust strongly modulated transmission of a T-shaped structure with local Rashba interaction

We propose a scheme of spin transistor that uses a T-shaped structure with a local Rashba interaction. A wide antiresonance energy gap appears due to the interplay of two types of interference: the Fano-Rashba interference and the structure interference. A large current from the gap area can be obtained via changing the Rashba strength and/or the length of the sidearm by using gate voltage. The robustness of the antiresonance gap against strong disorder is demonstrated and shows the feasibility of this structure for a real application.