TM_crossing
- ofiber.planar_step.TM_crossing(V, n1, n2, mode)[source]
Return the TM eigenvalue for a planar waveguide mode.
The eigenvalue, xi, satisfies the eigenvalue equation for the specified TM mode in a planar waveguide.
The solution is found numerically using the Brent method. The only tricky bit is setting the proper range to search within.
- Parameters:
V – the V-parameter for the waveguide
n1 – index of waveguide
n2 – index of material next to waveguide
mode – desired propagation mode
- Returns:
the eigenvalue. Returns 0 if no eigenvalue.