Experimental and numerical investigations of two-dimensional "Antiresonant Reflecting Optical Waveguides'' (ARROWs) based on AlGaAs/GaAs

The device concept of a two-dimensional ARROW and its technological realization is reported. ARROWs belong to the class of leaky Bragg waveguides in integrated optoelectronics.1 Despite core sizes of dc = 5 µm quasi-monomode waveguiding is achieved by reflection at Bragg layers. These layers operate in antiresonance for the fundamental mode, i.e., due to its optical path length the attenuation coefficient is rather small (typically α < 0.5 dB/ cm) for this mode only compared to every other leaky mode (typically α > 20 dB/cm). The device exhibits antiresonant guiding in both cross sectional dimensions, so the ARROW fundamental mode profile is similar in shape and size to that of a monomode glass fiber. Hence, efficient ARROW based fiber-chip coupling can be achieved with coupling coefficients of η ≃ 95%. We used AlGaAs/ GaAs as an exemplary material system.