wl0 1.55[um] "Design wavelength"
w_core wl0/5 "Core width"
h_core 1.2*w_core "Core height"
w_clad 10*w_core "Cladding width"
r0 3.1*w_clad "Radius of curvature"
dx 2.3*w_core "Separation between waveguides"
lda0 wl0 Wavelength
f0 c_const/lda0 Frequency
n_core 2.5 "Core refractive index"
n_clad 1.5 "Cladding refractive index"