GaAs/Ge/GaAs sublattice reversal epitaxy and its application to nonlinear optical devices

Abstract

We have proposed and demonstrated sublattice reversal epitaxy in lattice-matched GaAs/Ge/GaAs (1 0 0) and (1 1 1) systems using molecular beam epitaxy. For growth on (1 0 0) substrates misoriented toward [0 1 ̄ 1] , the overgrown GaAs layer had its sublattice reversed. For growth on (1 1 1) substrates, the overgrown GaAs of the (1 1 1)B type was reproducible whether the substrate orientation was (1 1 1)A or (1 1 1)B. Furthermore, sublattice reversal epitaxy has been applied to the fabrication of a periodically domain-inverted AlGaAs QPM waveguide. A preliminary second-harmonic generation demonstration exhibited quasi-phase-matched output at the fundamental wavelength of 1576.1 nm.