Sub-kT switching in asymmetric Y-transistors with internal feedback coupling

Abstract

We report on nonlinear transport phenomena in an asymmetric Y-transistor. The left branch acting as gate for the channel formed between the stem and the right branch of the Y-transistor is isolated from the branching section via a narrow constriction. The transfer characteristics of the Y-transistor is studied at low temperature in two configurations for which the stem is used either as drain contact or source contact. In the latter configuration, internal feedback coupling allows us to demonstrate subthreshold slopes 30% below the thermodynamic kT-limit for conventional field effect transistors.