Transmission through abrupt heterojunction potential barriers

A new expression is derived for the transmission coefficient of incident electrons scattered by a varying potential with discontinuities. The expression is applicable above, below, and near the potential peak. As an example, electron transmission across the energy barrier in the emitter of an InP/InGaAs heterojunction bipolar transistor is calculated. Excellent agreement with a numerical calculation is obtained, even for electron energies close to the potential peak, where other expressions fail. It is shown how this new approach reduces to other expressions in limiting cases, and its validity in comparison to other approximations is discussed.<
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