Recent advances in germanium emission [Invited]

Group IV Direct Band Gap Photonics: Methods, Challenges, and Opportunities

“…However, close to the center the strain profile alters the band structure with L-and γ-valley starting to cross, which allows for intervalley scattering (Boucaud et al, 2013) from a high-into a low-effective mass valley with a higher mobility, a process inverse to the Gunn effect (Gunn, 1963). This may support current extraction and injection in optical devices.…”

All‐Around SiN Stressor for High and Homogeneous Tensile Strain in Germanium Microdisk Cavities

“…Enhancing tensile strain transfer into Ge optical cavities is thus requested in order to signifi cantly decrease the lasing threshold, and different approaches have been proposed in the literature. [12][13][14] High level strain transfers have been evidenced using strained silicon nitride (SiNH referred to as SiN in the following) layers as stressor layers. [15][16][17][18][19][20] The use of stressor layers is widely investigated since it relies on a complementary metal oxide semiconductor (CMOS)-compatible process.…”

“…We have investigated the strain level at the top of these microdisks using a spatially resolved Raman spectroscopy in a confocal back-scattering confi guration. [ 13,24,25 ] For these measurements, the laser pump at 532 nm wavelength is focused on the disk surface using a ×100 objective (NA = 0.9). The sample is mounted on a piezo-electric stage allowing an in-plane step displacement of 400 nm.…”

Photoluminescence emission from a nanofabricated scanning probe tip made of epitaxial germanium

“…Also, the emission properties of Ge/Si are being investigated with the aim of obtaining laser emission from devices integrated on silicon chips. It is therefore expected that Ge/Si epitaxial wafers may become an important material for future optoelectronic applications [15,16,17,18,19]. …”