Grating-coupled mid-infrared light emission from tensilely strained germanium nanomembranes
APPLIED PHYSICS LETTERS, vol.103, no.20, 2013 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 103 Issue: 20
- Publication Date: 2013
- Doi Number: 10.1063/1.4830377
- Journal Name: APPLIED PHYSICS LETTERS
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- TED University Affiliated: No
Abstract
Mechanically stressed nanomembranes are used to demonstrate mid-infrared interband light emission from Ge within the 2.1-2.5 mu m atmospheric transmission window. Large biaxial tensile strain is introduced in these samples to convert Ge into a (near-) direct-bandgap semiconductor and to red-shift its luminescence. A diffractive array of Ge pillars is used to outcouple the long-wavelength interband radiation, which is otherwise primarily emitted in the sample plane. An order-of-magnitude strain-induced enhancement in radiative efficiency is also reported, together with the observation of luminescence signatures associated with photonic-crystal cavity modes. These results are promising for the development of silicon-compatible lasers for mid-infrared optoelectronics applications. (C) 2013 AIP Publishing LLC.