Abstract

Quasi-phase-matched second harmonic generation of blue light in optical waveguides is currently of great interest since it holds the potential for miniaturized blue light sources for various applications. Many fabrication methods for periodic domain inversion and waveguide formation have been investigated in several material systems.¹ The method of the periodically segmented KTP waveguide studied by the du Pont group² has certain advantages over the others: it forms the waveguides and the inverted domains in one processing step, and it offers greater degrees of freedom in waveguide fabrication. The segmented structure does not form a conventional waveguide since it consists of alternating guided and unguided sections; however, very low radiative loss was observed experimentally.³ The linear properties of this type of waveguide have not been studied so far. In this paper, we present results of numerical modeling of the linear propagation characteristics of the periodically segmented waveguides, which include propagation constants, radiative loss rates, and guided wave profiles of the fundamental and the second harmonic frequencies.

© 1992 Optical Society of America