LCML - Phase shifter based on PN junction | lcml_ps_pn_1550



This PN junction phase shifter model is built based on MODE Solutions and DEVICE simulation results.

Example Test File

phase_shift_pn.icp (340.5 KB)

User Guide

lcml_ps_pn_1550 (ps)

LCML: p-n junction phase shifter.


Name Type
ele_an Electrical Signal
ele_cat Electrical Signal
opt_1 Optical Signal
opt_2 Optical Signal


Name Default value Default unit Range
note - Voltage limit: [-4.25 V, 0.5 V].
- If the input is outside the limits, the model will use the
upper/lower limit values for the simulation.
-- --
wg_length 1 mm [0, 10]

Model Development

Parameter extraction
Please refer to the [Traveling Wave Modulator (TWM)] ( page for detailed information on the component level simulations using DEVICE and MODE Solutions.


  1. In INTERCONNECT, create a compound element.

  2. Add two bidirectional optical ports namely “opt_1” (left) and “opt_1” (right) and two bidirectional electrical ports namely “ele_an” and “ele_cat” (both on top) and auto-arrange their positions.

  3. Expand the compound element, and add the following elements: MODE Waveguide (2), Optical Modulator Measured, Electrical Adder, and Electrical Constant Multiplier. Arrange and connect them as shown below:

  4. Add a new property “wg_length” to the compound element (default value is 1 mm in this example). Set the “model” to be “lcml_ps_pn_1550” and “prefix” to be “ps”.

  5. Edit the Optical Modulator Measured element and load the twmod_neff_V.dat file. This file can be found in the LCML_resource folder from the download page. This file contains a table that describes the effective index change as a function of voltage. For more information on the file format, please refer to the [Optical Modulator Measured (OM)] ( page. For more information on the parameter extraction workflow using component level simulations tools (DEVICE and MODE Solutions), please refer to the [Traveling Wave Modulator (TWM)] ( page.

  6. Edit the MODE Waveguide elements and load the rib_waveguide_wo_mode_profile.ldf file. This file was exported from MODE Solutions (disable the “np” NPDensityGridAttribute object in tw_modulator.lms and run a frequency sweep).

  7. Back to the compound element. In the setup script of the compound, write the following script commands to define the length of the MODE Waveguide and Optical Modulator Measured elements. Finally, set icon.

       setnamed("OM_1","length", wg_length);


Download the simulation file phase_shifter_pn.icp from the top of this page. In this simulation file, the phase shifter is 5 mm long and it is measured by an Optical Network Analyzer (ONA). Run the sweep object “sweep” defined in the project file. It will sweep through the applied voltage to the phase shifter hence result in different phase shift and loss values in the shiftter. When the sweep is complete, right click on the sweep object and choose to visualize the results. The result “phase” is plotted below.

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