Demonstration of a DFB laser with an integrated electro-absorption modulator produced using a novel quantum-well intermixing technique

Bandgap engineering is used extensively in the telecommunications field. Quantum well intermixing (QWI) is a post-growth method of bandgap engineering that has been studied for the integration of photonic devices (Marsh et al., J. Vac. Sci. Technol. A16 (1998) 810). A novel method of QWI has been discovered that uses layers of indium phosphide grown by helium-plasma-assisted gas source molecular beam epitaxy, subsequently referred to as He*-InP, in combination with thermally induced QWI. The He*-InP has been shown to contain large numbers of defects that can act as fast non-radiative recombination centres. These can be used with the thermally induced QWI to produce regions with a larger bandgap and containing the fast, non-radiative defect centres. This novel intermixing process has been used to fabricate integrated distributed feedback lasers and electro-absorption modulators.