title: Efficient Single-Mode GaAs/AlGaAs W Waveguide Phase Modulator with a Low Propagation Loss.
abstract: We report a single-mode P-P-p-i-n-N-N GaAs/AlGaAs W waveguide phase modulator with a high phase modulation efficiency and a low propagation loss. The phase modulator with a W-shaped refractive-index profile utilizes a novel epilayer structure to reduce the propagation loss associated with doped layers and to obtain a phase modulation efficiency larger than those of P-i-N double heterostructure modulators. The phase shift and propagation loss were measured with a Fabry-Perot resonance method at 1.31-mum wavelength. A phase modulation efficiency as high as 34.6 degrees /V mm was measured for TE polarized light. Also propagation losses of less than 0.6 dB/cm were achieved. As a result, the W waveguide phase modulator that exhibits a high phase modulation efficiency and a low propagation loss have been experimentally realized for the first time as far as we know.
authors.forename: Y T
authors.initials: YT
authors.lastname: Byun
authors.forename: K H
authors.initials: KH
authors.lastname: Park
authors.forename: S H
authors.initials: SH
authors.lastname: Kim
authors.forename: S S
authors.initials: SS
authors.lastname: Choi
authors.forename: J C
authors.initials: JC
authors.lastname: Yi
authors.forename: T K
authors.initials: TK
authors.lastname: Lim