NEAR-RESONANCE ACOUSTOOPTICAL INTERACTIONS IN GAAS AND INP

Acousto-optical properties of GaAs and InP are thoroughly investigated for photon energies tending to the band gap from below, and the whole set of photoelastic constants is determined as a function of the wavelength lambda for lambda less-than-or-equal-to 1.06 mum. Figures of merit as high as 1200 times those of silica have been measured. It is shown how one can take advantage of the near-resonance acousto-optical properties of GaAs and InP in device design, in spite of the optical absorption. Such devices could be broadband, fast, compact, and insensitive to light polarization and may involve other direct-gap III-V crystals, adapted to the laser radiation.