Directly modulated membrane-buried heterostructure lasers on SiO2/Si substrate (Conference Presentation)

Abstract

Reduction of laser operating energy is a key issue to use the lasers in datacom and computercom networks because internet traffic is still increasing. To reduce operating energy, it is important to increase the optical confinement factor because the modulation efficiency is proportional to square root of optical confinement factor. Thus, the integration of thin membrane laser on SiO2/Si substrate is essential. Employing buried heterostructure (BH), in which the active region is buried with InP layer, is also important because BH provides efficient carrier confinement and thermal conductance. For datacom application, we have developed membrane Distributed Reflector (DR) laser array on SiO2/Si substrate. To fabricate BH, we have employed epitaxial growth of InP layer on a directly bonded InP on SiO2/Si substrate. We demonstrated an 8-channel DR laser array with integrating an SiN arrayed waveguide grating (AWG) filter. We have also developed photonic crystal (PhC) wavelength-scale cavity laser to obtain ultra-low operating energy for computercom application. The device exhibited a threshold current of 22 A, and a 7.3-fJ/bit energy cost directly modulated with a 10-Gbit/s NRZ signal. These results indicate that the membrane BH lasers on SiO2/Si substrate are highly suitable for use as a transmitter in datacom and computercom applications.