Valley selective tunneling transistor based on valley discontinuities in AlGaAs heterostructures

Abstract

The conduction‐band discontinuities in AlxGa1−xAs/AlyGa1−yAs heterostructure for various valleys (Γ, L, X) are utilized to conceive of a valley selective tunneling transistor. At low temperature, the perpendicular tunneling current is very small because of the large Γ‐Γ discontinuity and the small prefactor for Γ to X tunneling. However, if the valley population is altered by applying a lateral bias to the emitter, one can dramatically alter the perpendicular current since the X‐X discontinuity is nonexistent and the L‐L discontinuity is very small. By choosing proper values of x and y in the heterostructure, a very large current (power) change can be produced in the on and off states.