This study probes the extent to which dislocations reduce carrier lifetimes and alter growth morphology and luminescence in InAs quantum dots (QD) grown on silicon. These heterostructures are key ingredients to achieving a highly reliable monolithically integrated light source on silicon necessary for photonic‐integrated circuits. Around 20%–30% shorter carrier lifetimes are found at spatially resolved individual dislocations at room temperature using time‐resolved cathodoluminescence spectroscopy, highlighting the strong nonradiative impact of dislocations even against the three‐dimensional confinement of QDs. Beyond these direct effects of increased nonradiative recombination, it is found that misfit dislocations in the defect filter layers employed during III–V/Si growth alter the QD growth environment to induce a crosshatch‐like variation in QD emission color and intensity when the filter layer is positioned sufficiently close to the QD emitter layer. Sessile threading dislocations generate even more egregious hillock defects that also reduce emission intensities by altering layer thicknesses, as measured by transmission electron microscopy and atom probe tomography. This work presents a more complete picture of the impacts of dislocations relevant to the development of light sources for scalable silicon photonic integrated circuits.
A pair of stacked two-dimensional heterostructures suitably rotated with respect to each other support exotic electronic properties with interesting implications for nanoelectronics and quantum technologies. A similar paradigm can be extended to light, offering a great promise for emerging low-dimensional nanophotonic heterostructures. In this Opinion article, we discuss emerging photonic responses enabled by twisting and stacking suitably tailored nanostructures. We discuss how the multi-physics interactions of light with matter in twisted bilayers can tailor their photonic response and engineer light dispersion in extreme ways. We conclude by providing an outlook on this emerging field of research and its potential for classical and quantum light manipulation at the nanoscale.
more » « less- NSF-PAR ID:
- 10220941
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 11
- Issue:
- 5
- ISSN:
- 2159-3930
- Page Range / eLocation ID:
- Article No. 1377
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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