Germanium Band Gap Engineering Induced by Tensile Strain for Si-Based Optoelectronic Applications

Tensile strain engineering of germanium micro-disks on free-standing SiO2 beams

Ge-Photodetectors for Si-Based Optoelectronic Integration

High speed photodetectors are a key building block, which allow a large wavelength range of detection from 850 nm to telecommunication standards at optical fiber band passes of 1.3-1.55 μm. Such devices are key components in several applications such as local area networks, board to board, chip to chip and intrachip interconnects. Recent technological achievements in growth of high quality SiGe...

Strain-Induced Band Gap Engineering in Selectively Grown GaN-(Al,Ga)N Core-Shell Nanowire Heterostructures.

We demonstrate the selective area growth of GaN-(Al,Ga)N core-shell nanowire heterostructures directly on Si(111). Photoluminescence spectroscopy on as-grown nanowires reveals a strong blueshift of the GaN band gap from 3.40 to 3.64 eV at room temperature. Raman measurements relate this shift to compressive strain within the GaN core. On the nanoscale, cathodoluminescence spectroscopy and scann...

Tensile Strain of Germanium Micro-Disks on Freestanding SiO2 Beams

Tensile strain is crucial to expect the direct recombination in germanium (Ge), towards monolithic light sources on silicon (Si). Freestanding beams of Ge are known to produce strong tensile strain, however, it is not trivial to construct a cavity in a freestanding structure. Here, we fabricated Ge micro-disks on freestanding oxide beams, and observed Whispering-Gallery-Modes (WGM) by photolumi...

Band-gap engineering by molecular mechanical strain-induced giant tuning of the luminescence in colloidal amorphous porous silicon nanostructures.

Nano-silicon is a nanostructured material in which quantum or spatial confinement is the origin of the material's luminescence. When nano-silicon is broken into colloidal crystalline nanoparticles, its luminescence can be tuned across the visible spectrum only when the sizes of the nanoparticles, which are obtained via painstaking filtration methods that are difficult to scale up because of low...