Semiconductor light emitters compatible with standard Si integration technology (SIT) are of particular interest for overcoming limitations in the operating speed of microelectronic devices 1-3. Light sources based on group-IV elements would be SIT compatible but suffer from the poor optoelectronic properties of bulk Si and Ge. Here, we demonstrate that epitaxially grown Ge quantum dots (QDs) in a fully coherent Si matrix show extraordinary optical properties if partially amorphised by Ge-ion bombardment (GIB). The GIB-QDs exhibit a quasi-direct-band gap and show, in contrast to conventional SiGe nanostructures, almost no thermal quenching of the photoluminescence (PL) up to room-temperature (RT). Microdisk resonators with embedded GIB-QDs exhibit threshold-behaviour and super-linear increase of the integrated PL-intensity (IPL) with increasing excitation power Pexc which indicates light amplification by stimulated emission in a fully SIT-compatible group-IV nano-system.
@article{arxiv.1505.03380,
title = {Efficient room-temperature light-emitters based on partly amorphised Ge quantum dots in crystalline Si},
author = {M. Grydlik and F. Hackl and H. Groiss and M. Glaser and A. Halilovic and T. Fromherz and W. Jantsch and F. Schäffler and M. Brehm},
journal= {arXiv preprint arXiv:1505.03380},
year = {2016}
}