Title :
Norm-conserving finite-difference beam-propagation method for TM wave analysis in step-index optical waveguides
Author :
Yamauchi, Junji ; Matsubara, Kenji ; Tsuda, Takeshi ; Nakano, Hisamatsu
Author_Institution :
Coll. of Eng., Hosei Univ., Tokyo, Japan
fDate :
5/1/2000 12:00:00 AM
Abstract :
Nonconservation of power is a perplexing problem in the propagating beam analysis of transverse magnetic (TM) waves in a z-variant step-index optical waveguide. To conserve the power in terms of a squared norm, a modified finite-difference (FD) formula is introduced that allows a general position of a core-cladding interface. The use of the modified formula contributes to a reduction in a field profile error caused by a staircase approximation with subsequent conservation of power, particularly for a symmetrical waveguide. To obtain the power conservation even in the analysis of an asymmetrical waveguide, a z-derivative of the refractive index is taken into account. An asymmetrical taper and tilted waveguides placed in parallel are investigated to validate the present technique.
Keywords :
finite difference methods; integrated optics; optical waveguide theory; optical waveguides; symmetry; TM wave analysis; asymmetrical taper; asymmetrical waveguide; core-cladding interface; field profile error; modified finite-difference formula; norm-conserving finite-difference beam-propagation method; power conservation; power nonconservation; propagating beam analysis; refractive index; slab waveguides; squared nor; staircase approximation; step-index optical waveguides; symmetrical waveguide; tilted waveguides; transverse magnetic waves; z-derivative; z-variant step-index optical waveguide; Benchmark testing; Equations; Finite difference methods; Magnetic analysis; Optical beams; Optical propagation; Optical refraction; Optical variables control; Optical waveguides; Slabs;
Journal_Title :
Lightwave Technology, Journal of
