Resonant tunneling of electrons in AlSb/GaInAsSb double barrier quantum wells

We have studied the optical and electronic transport properties of n-type AlSb/GaInAsSb double barrier quantum well resonant tunneling diodes (RTDs). The RTDs were grown by molecular beam epitaxy on GaSb substrates. Collector, quantum well, and emitter regions are comprised of the lattice-matched quaternary semiconductor Ga0.64In0.36As0.33Sb0.67. Photoluminescence emission spectra reveal a direct bandgap semiconductor with a bandgap energy of Eg approximate to 0.37 eV, which corresponds to a cut-off wavelength of lambda approximate to 3.3 mu m. The composition-dependent bandgap energy is found to follow Shim's model. At room temperature, we observe resonance current densities of jres=0.143 kA cm(-2) with peak-to-valley current ratios of up to PVCR=6.2. At cryogenic temperatures T<50 K, the peak-to-valley current ratio increases up to PVCR=16.