Optical Properties of Tensilely Strained Ge Nanomembranes
AbstractGroup-IV semiconductors, which provide the leading materials platform of micro- electronics, are generally unsuitable for light emitting device applications because of their indirect- bandgap nature. This property currently limits the large-scale integration of electronic and photonic functionalities on Si chips. The introduction of tensile strain in Ge, which has the effect of lowering the direct conduction-band minimum relative to the indirect valleys, is a promising approach to address this challenge. Here we review recent work focused on the basic science and technology of mechanically stressed Ge nanomembranes, i.e., single-crystal sheets with thicknesses of a few tens of nanometers, which can sustain particularly large strain levels before the onset of plastic deformation. These nanomaterials have been employed to demonstrate large strain-enhanced photoluminescence, population inversion under optical pumping, and the formation of direct-bandgap Ge. Furthermore, Si-based photonic-crystal cavities have been developed that can be combined with these Ge nanomembranes without limiting their mechanical flexibility. These results highlight the potential of strained Ge as a CMOS-compatible laser material, and more in general the promise of nanomembrane strain engineering for novel device technologies. View Full-Text
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Paiella, R.; Lagally, M.G. Optical Properties of Tensilely Strained Ge Nanomembranes. Nanomaterials 2018, 8, 407.
Paiella R, Lagally MG. Optical Properties of Tensilely Strained Ge Nanomembranes. Nanomaterials. 2018; 8(6):407.Chicago/Turabian Style
Paiella, Roberto; Lagally, Max G. 2018. "Optical Properties of Tensilely Strained Ge Nanomembranes." Nanomaterials 8, no. 6: 407.
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