Intraband Auger effect in InAs∕InGaAlAs∕InP quantum dot structures

Abstract

InAs quantum dot structures grown on InGaAlAs have been investigated for midinfrared photodetection. Intraband photocurrent and absorption measurements, together with a full three-dimensional theoretical modeling revealed that a bound-to-bound optical transition, where the final state is about 200meV deep below the conduction band continuum, is responsible for the photogenerated current. The reported results strongly suggest that an Auger process plays a fundamental role in generating the observed intraband photocurrent. Photoluminescence and interband photocurrent spectra of the same structures further support the reached conclusions.

Temperature dependence of quantum efficiency in Quantum Dot Infrared Photodetectors

“…This indicates other effects might also be crucial to the QE of QDIPs. It has been suggested that the intraband Auger interaction can help to extract the carrier out of QDs [15]. Such effect requires two electrons at excited states and one empty lower state.…”

Multiple-photon peak generation near the ˜10 μm range in quantum dot infrared photodetectors

“…However, scattering processes from interactions between the electronic carriers are not accounted for in our calculations, whence the importance of the multiphoton results given here relative to ones that might come from interactions (like Auger scattering), cannot be settled in this article, although it has been suggested by two of us in Ref. 13, we recall, nonetheless, that the carrier densities of the samples are quite low, which intuitively suggests that dynamical effects due to interelectronic interactions should be minimal.…”

“…It has been conjectured in Ref. 13 that higher order processes due to electron-electron interactions, specifically the Auger scattering, might be responsible for the appearance of the peaks. We see here, however, by using a single-electron model, that it is possible to reproduce the observed photocurrent peaks and all their main trends, leading to an alternative explanation in terms of multiple photon processes.…”

Photo and dark current noise in self-assembled quantum dot infrared photodetectors

“…Quantum dot infrared photodetectors have attracted more and more attention in the last years since they are expected to reach higher gains and exhibit lower dark current than QWIPs. Furthermore they are sensitive to normally incident infrared radiation not requiring special optical coupling [1][2][3][4][5][6][7][8][9][10].…”