Temperature-Dependent Photoluminescence Characteristics of GeSn Epitaxial Layers

  title={Temperature-Dependent Photoluminescence Characteristics of GeSn Epitaxial Layers},
  author={Fabio Pezzoli and Anna Giorgioni and David Patchett and Maksym Myronov},
  journal={ACS Photonics},
Ge1–xSnx epitaxial heterostructures are emerging as prominent candidates for the monolithic integration of light sources on Si substrates. Here we propose a suitable explanation for their temperature-dependent photoluminescence (PL) that is based upon the so far disregarded optical activity of dislocations. By working at the onset of plastic relaxation, which occurs whenever the epilayer releases the strain accumulated during growth on the lattice-mismatched substrate, we demonstrate that… 

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