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arXiv · 1202.3530

Electroluminescence from Strained Ge membranes and Implications for an Efficient Si-Compatible Laser

Donguk Nam·David Sukhdeo·Szu-Lin Cheng·Arunanshu Roy·Kevin Chih-Yao Huang·Mark Brongersma·Yoshio Nishi·Krishna Saraswat
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Abstract

We demonstrate room-temperature electroluminescence (EL) from light-emitting diodes (LED) on highly strained germanium (Ge) membranes. An external stressor technique was employed to introduce a 0.76% bi-axial tensile strain in the active region of a vertical PN junction. Electrical measurements show an on-off ratio increase of one order of magnitude in membrane LEDs compared to bulk. The EL spectrum from the 0.76% strained Ge LED shows a 100nm redshift of the center wavelength because of the strain-induced direct band gap reduction. Finally, using tight-binding and FDTD simulations, we discuss the implications for highly efficient Ge lasers.

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Donguk Nam, David Sukhdeo, Szu-Lin Cheng, Arunanshu Roy, Kevin Chih-Yao Huang, Mark Brongersma, Yoshio Nishi, Krishna Saraswat. 2012-02-16. Electroluminescence from Strained Ge membranes and Implications for an Efficient Si-Compatible Laser. https://doi.org/10.1063/1.3699224

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