Electron-wave reflection by multi-quantum barrier in n-GaAs/i-AlGaAs/ n-GaAs tunneling diode

For the purpose of experimentally demonstrating the enhancement of electron-wave reflection by a multi-quantum barrier (MQB) consisting of multiple combinations of quarter de Broglie wavelength hetero-stacks, we have fabricated two types of n-GaAs/i-barrier/n-GaAs tunneling diodes with a bulk AlxGa1−xAs barrier and an AlxGa1−xAs/GaAs MQB. From the current-voltage characteristic at 77 K, it has been clarified that electrons are well reflected by the MQB. The potential barrier height, virtually increased by the MQB, is estimated to be about 80 meV, which is in good agreement with a theoretical expectation.