PHONON-ASSISTED TUNNELING AND PEAK-TO-VALLEY RATIO IN A MAGNETICALLY CONFINED QUASI-ZERO-DIMENSIONAL INGAAS INALAS RESONANT-TUNNELING DIODE/

We studied phonon-assisted tunneling and the peak-to-valley ratio (P/V ratio) of magnetically confined ''dot-like'' electron systems in an I nGaAs/InAlAs triple barrier resonant tunneling diode. We observe phono n bottleneck, i.e., suppression of the nonresonant valley current and two mode narrow band GaAs- and AlAs-like longitudinal optical (LO)-pho non-assisted tunneling peaks. The P/V ratio increases remarkably with the magnetic confinement and has a maximum each time the energy separa tion of the confined states matches the GaAs-LO-phonon energy.