Modeling femtosecond pulses in optical power splitter using time domain techniques

In this paper, time domain beam propagation method (TD-BPM) has been developed and implemented for analyzing short and ultra short pulse interaction inside optical power splitter. The results obtained by the technique has been compared to that of the finite difference time domain (FDTD) technique. The TD-BPM is as effective and stable on the properly designed device as on waveguide and directional coupler. Proper design of the device ensures minimum radiation loss enhancing the output power. Moreover, the TD-BPM provides complete visualization of the pulse in course of its propagation as the technique updates the spatiotemporal pulsed window with propagation step, unlike the FDTD where finely gridded device is updated with time. Being an implicit technique, it is free from Courant–Friedrich–Levy constraint and infinitesimal gridding.