Related Experiment Video
Updated: Apr 17, 2026

09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
10.4K
Two-mode de/multiplexer based on multimode interference couplers with a tilted joint as phase shifter.
Optics Letters
|February 14, 2015
Summary
This study introduces a compact two-mode de/multiplexer (DE/MUX) using multimode interference (MMI) couplers and a novel tilted joint phase shifter (PS). This design enhances fabrication tolerance and maintains excellent performance, making it suitable for optical communication systems.
Area of Science:
- Photonics
- Optical Engineering
- Integrated Optics
Background:
- Multimode interference (MMI) devices are crucial for optical signal processing.
- Traditional phase shifters (PS) in MMI-based de/multiplexers (DE/MUX) require stringent fabrication, limiting practical applications.
- Improving fabrication tolerance and device compactness is essential for advancing MMI-based optical devices.
Purpose of the Study:
- To propose a novel design for a two-mode de/multiplexer (DE/MUX) utilizing multimode interference (MMI) couplers.
- To replace conventional narrow strip waveguide phase shifters (PS) with a more robust tilted joint.
- To enhance the fabrication tolerance and reduce the size of MMI-based DE/MUX devices while maintaining high performance.
Main Methods:
- A novel two-mode de/multiplexer (DE/MUX) design based on multimode interference (MMI) couplers was developed.
- A tilted joint was implemented as a phase shifter (PS) to mitigate fabrication errors.
- Device performance was evaluated through simulations.
Main Results:
- The proposed MMI-based DE/MUX achieves a compact size of 39.54 μm.
- The device exhibits a large fabrication tolerance of ±25 nm.
- Simulations demonstrate low de-multiplexing crosstalk (< -28 dB) and insertion loss (< 1.0 dB) across the C-band.
Conclusions:
- The novel MMI-based DE/MUX design with a tilted joint phase shifter offers improved fabrication tolerance and compactness.
- The device achieves excellent optical performance, including low crosstalk and insertion loss.
- This design presents a promising solution for efficient optical signal processing in integrated photonic circuits.
More Related Videos
Related Concept Videos
Impedance Combination
907
Consider a string of christmas lights, each bulb symbolizing an impedance element. In this series configuration, the flow of electric current remains uniform across every component. This behavior aligns with Kirchhoff's Voltage Law (KVL), which asserts that the total impedance in such a setup equals the sum of individual impedances—akin to resistors in series. It follows that the voltage from the power source is distributed proportionally among these components, adhering to the voltage...
907
Design Example: Capacitance Multiplier Circuit
1.8K
In integrated circuit technology, a capacitance multiplier is often utilized to produce a larger capacitance value when a small physical capacitance falls short. This is achieved by a circuit that multiplies capacitance values by a factor of up to 1000, such that a 10-pF capacitor can replicate the performance of a 100-nF capacitor.
The circuit illustrated in Figure 1 below incorporates two op-amps, with the first operating as a voltage follower and the second acting as an inverting amplifier.
The circuit illustrated in Figure 1 below incorporates two op-amps, with the first operating as a voltage follower and the second acting as an inverting amplifier.
1.8K
Phase Contrast and Differential Interference Contrast Microscopy
15.3K
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
15.3K
Biasing of Metal-Semiconductor Junctions
863
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
863
Bus Impedance Matrix
593
Calculating subtransient fault currents for three-phase faults in an N-bus power system involves using the positive-sequence network. When a three-phase short circuit occurs at a specific bus, the analysis uses the superposition method to evaluate two separate circuits.
In the first circuit, all machine voltage sources are short-circuited, leaving only the prefault voltage source at the fault location. The positive-sequence bus impedance matrix can be determined by solving the nodal equations,...
In the first circuit, all machine voltage sources are short-circuited, leaving only the prefault voltage source at the fault location. The positive-sequence bus impedance matrix can be determined by solving the nodal equations,...
593
Series Impedances: Three-Phase Line
533
Calculating series impedances for a three-phase overhead line involves evaluating resistances and inductive reactances in a network with three-phase and multiple neutral conductors grounded at regular intervals.
Using Kirchhoff's laws, an integro-differential equation for the network is derived. This equation accounts for unbalanced phase currents, which may induce return currents through neutral wires and the earth, seeking the least impedance path. Earth return conductors can replace the...
Using Kirchhoff's laws, an integro-differential equation for the network is derived. This equation accounts for unbalanced phase currents, which may induce return currents through neutral wires and the earth, seeking the least impedance path. Earth return conductors can replace the...
533

