k∥ = 0 filtering effects in ballistic electron transport through sub-surface GaAs-AlGaAs double barrier resonant tunneling structures

In ballistic electron emission microscopy on Au-GaAs double barrier resonant tunneling diodes, electrons are transferred across an interface between an area of high and low effective mass and subsequently through a low-dimensional state. Experimentally, the resonant level in the double barrier structure becomes evident as clear step in the ballistic current measured as a function of sample bias. To analyze the spectrum, an extended transfer matrix method, together with the commonly accepted Bell Kaiser model is used. In terms of this model we show that only electrons with zero wave vector parallel to the barriers can be transmitted resonantly.