siph_phshifter :
An optical phase shifter element.

The siph_phshifter primitive represents an optical phase shifter, which propagates the optical waves with a variable delay controlled by the xreal-typed input ‘delay. For optical waves, this delay is equivalent to a phase shift equal to delay*2*PI*c0/wavelength, where c0 is the speed of light in free space.

The parameter Zrel specifies the phase shifter’s characteristic impedance relative to a reference impedance (Z0) of your choice. Note that the use of this relative impedance allows one to determine the amount of reflections at impedance discontinuities without having to know the absolute values of the characteristic impedances. While the choice of the reference impedance (Z0) can be arbitrary, it must be consistent across all the silicon-photonic components used in a system. In other words, all the equivalent circuit elements describing the impedance relationships at the optical ports must use the impedance values relative to the same Z0.

The parameter gain and dispersion specifies the total gain and group delay dispersion (GDD) through the phase shifter. For more information on these parameters, please refer to the documentation on the siph_waveguide primitive.

Input/Output Terminals

Name	I/O	Type	Description
port_1	input	xreal	optical port #1
port_2	input	xreal	optical port #2
delay	input	xreal	group delay

Parameters

Name	Type	Default	Unit	Description
Zrel	real	1.0	None	relative characteristic impedance
gain	real	1.0	None	gain
dispersion	real	0.0	second^2	group delay dispersion
wavelength	real	1550e-9	meters	center wavelength