Micro Ring Resonator (MRR)

We use SiEPIC EBeam library in this tutorial.

This notebook walks through the process of setting up and simulating a micro ring resonator device using the OPICS package.

A ring resonator consists of an optical waveguide which is looped back on itself, such that a resonance occurs when the optical path length of the resonator is exactly a whole number of wavelengths. In simple terms, an all pass ring resonator can be thought of consisting input/output components, evanescent coupling region like a directional coupler, and a waveguide (as shown below).

import time
import warnings
import numpy as np
from opics.globals import c
from opics import Network
import opics

freq = np.linspace(c * 1e6 / 1.5, c * 1e6 / 1.6, 2000)

Import component library

Import ebeam library from libraries module.

ebeam = opics.libraries.ebeam

Define network

Create an instance of Network class, which is used to add, connect, and simulate circuit components.

circuit_name = "mrr"
circuit = opics.Network(circuit_name)

Add circuit components

Add grating couplers, evanescent coupler (e.g. directional coupler halfring), and a waveguide. You can define custom frequency data points for a component as well (see the example for output_GC).

input_gc = circuit.add_component(ebeam.GC(freq))
output_gc = circuit.add_component(ebeam.GC(freq))
wg = circuit.add_component(ebeam.Waveguide(freq, np.pi*5e-6))
dc_halfring = circuit.add_component(ebeam.DC_halfring(freq))

Define circuit connectivity

In this section, we define the component connections. The connections are defined using Network.connect, e.g.Network.connect(component1, component1_port, component2, component2_port)

#connect components
circuit.connect(input_gc, 1, dc_halfring, 0)
circuit.connect(dc_halfring, 1, wg, 0)
circuit.connect(wg, 1, dc_halfring, 3)
circuit.connect(dc_halfring,2, output_gc,1)

Simulate the circuit

warnings.filterwarnings('ignore') #ignore all/complex number warnings from numpy or scipy
sim_start = time.time()

#simulate network
circuit.simulate_network()

print("simulation finished in %ss"%(str(round(time.time()-sim_start,2))))

simulation finished in 0.05s

Visualize the simulation result

circuit.sim_result.plot_sparameters(show_freq = False, scale="abs_sq", ports = [[1,0], [0,0]])