Title :
Optical design of evanescently coupled, waveguide-fed photodiodes for ultrawide-band applications
Author :
Giraudet, L. ; Banfi, F. ; Demiguel, S. ; Herve-Gruyer, G.
Author_Institution :
Groupement d´Interet Econ., OPTO+, Marcoussis, France
Abstract :
Beam propagation method simulation shows that evanescently coupled waveguide/photodiodes can be optimized to have absorption lengths as short as butt-coupled photodiodes. Efficient focalization of optical power in the absorber is achievable by appropriate choice of layer geometry and refractive index. Two AlGaInAs-GaInAs structures have been designed for ultrawide-band operation at 60 and 100 GHz: these devices exhibit internal quantum efficiency as high as 94% and 75%, respectively, at 1.55-μm wavelength. Such promising performances are suitable for the realization of high-speed high-efficiency integrated photoreceivers with applications to millimeter-wave optical fiber links.
Keywords :
III-V semiconductors; aluminium compounds; broadband networks; gallium arsenide; indium compounds; optical design techniques; optical receivers; optical waveguides; photodiodes; refractive index; 1.55 mum; 100 GHz; 60 GHz; 75 percent; 94 percent; AlGaInAs-GaInAs; AlGaInAs-GaInAs structures; absorber; absorption lengths; beam propagation method simulation; butt-coupled photodiodes; evanescently coupled waveguide; evanescently coupled waveguide-fed photodiodes; focalization; high-speed high-efficiency integrated photoreceivers; internal quantum efficiency; layer geometry; millimeter-wave optical fiber links; optical design; optical power; refractive index; ultrawide-band applications; ultrawide-band operation; Absorption; High speed optical techniques; Optical coupling; Optical design; Optical propagation; Optical refraction; Optical surface waves; Optical waveguides; Optimization methods; Photodiodes;
Journal_Title :
Photonics Technology Letters, IEEE
