Assessing Carrier Recombination Processes in Type-II SiGe/Si(001) Quantum Dots
| Authors | |
|---|---|
| Year of publication | 2019 |
| Type | Article in Periodical |
| Magazine / Source | Annalen der Physik (Berlin) |
| MU Faculty or unit | |
| Citation | |
| Web | https://onlinelibrary.wiley.com/doi/epdf/10.1002/andp.201800259 |
| Doi | http://dx.doi.org/10.1002/andp.201800259 |
| Keywords | SiGe/Si;kvantove tecky;rekombinacni procesy;kp teorie |
| Description | In this work, it is shown how different carrier recombination paths significantly broaden the photoluminescence (PL) emission bandwidth observed in type-II self-assembled SiGe/Si(001) quantum dots (QDs). QDs grown by molecular beam epitaxy with very homogeneous size distribution, onion-shaped composition profile, and Si capping layer thicknesses varying from 0 to 1100 nm are utilized to assess the optical carrier-recombination paths. By using high-energy photons for PL excitation, electron-hole pairs can be selectively generated either above or below the QD layer and, thus, clearly access two radiative carrier recombination channels. Fitting the charge carrier capture-, loss- and recombination-dynamics to PL time-decay curves measured for different experimental configurations allows to obtain quantitative information of carrier capture-, excitonic-emission-, and Auger-recombination rates in this type-II nano-system. |
| Related projects: |
|