# LCML - Mach-Zehnder modulator | lcml_mod_mzi_1550

#1

This Mach-Zehnder Modulator (MZM) model is built based on a sub-circuit that includes several components, such as the PN phase shifter (lcml_ps_pn_1550).

## Example Test File

mzi_modulator.icp (942.0 KB)

User Guide

lcml_mod_mzi_1550 (mzm)

LCML: Mach-Zehnder modulator.

Ports

 Name Type ele_an_1 Electrical Signal ele_an_2 Electrical Signal ele_cat_1 Electrical Signal ele_cat_2 Electrical Signal opt_1 Optical Signal opt_2 Optical Signal

CML/Modulator

 Name Default value Default unit Range note - The arm with the "L" is longer.- 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. -- --

## Model Development

INTERCONNECT

1.In INTERCONNECT, create a compound element.

2.Add 2 bidirectional optical ports, namely “opt_1” (left) and “opt_1” (right), and 4 bidirectional electrical ports, namely “ele_an1” and “ele_cat1” (both on top), “ele_an2” and “ele_cat2” (both on bottom). Arrange their positions.

3.Set the “model” to “lcml_mod_mzi_1550” and “prefix” to “mzm”.

4.Expand the compound element, and add the following elements: primitive MODE Waveguide (2), primitive Waveguide Y Branch (2), LCML PN phase shifter - lcml_ps_pn_1550 (2), and primitive VD LP RC Filter (4). Set the properties of the MODE Waveguides and PN phase shifters according to the following table.

Elements Parameter Value Unit
WGD_1 length 200 μm
ldf filename rib_waveguide_wo_mode_profile.ldf
WGD_2 length 100 μm
ldf filename rib_waveguide_wo_mode_profile.ldf
PS_X(1-2) length 5 mm
LPF_X(1-4) measurement
1 2
1 0 5e+09
2 1 7.5e+09
3 2 1e+10
4 3 51.25e+10
5 4 1.5e+10
Arrange and connect them as shown below:

5.Back to the compound element and set icon.

## Test

Download the simulation file mzi_modulator.icp from the top of this page. In this simulation file, the MZM is measured by an Optical Network Analyzer (ONA). The following plot is the gain curves for -4 V and 0 V of driving voltage to port “ele_an_1”, respectively. The transmission shows that around a pi phase shift can be achieved in the modulator.

Optical Transceiver using LCML
Lumerical Compact Model Library (LCML)