Generation of New Colors of Light from a Nanophotonic Device

What if we could shine a red laser onto something and create another color of light or even a broad spectrum like a rainbow? These phenomena are the result of nonlinear light-matter interactions. The generated light can be used in applications such as biological molecule detection, ultra-high speed communications, and even exoplanet discovery.

Hvad går øvelsen ud på?

When you shine a red laser onto most things, usually you will see a red spot. This means that the frequency (or color) of light stays the same.

What if we could shine the same red light onto some material and see another color, like green or blue, or even a rainbow of colors?

The generation of new colors is possible thanks to nonlinear light-matter interactions, which are described by a certain type of mathematical model. In this exercise, we will first describe how new colors can be made from a single-color source and then create a rainbow of colors (a supercontinuum) using a tiny device that is smaller than your eyelash.

The supercontinuum can be used in a wide range of applications, including detection of biomolecules, advanced fiber-optic communications, and discovery of exoplanets. 

Hvordan foregår øvelsen?

  • Introduction to the idea of nonlinear phenomena from a mathematical and physical perspective, using slides and whiteboard. Topics covered will include: the nonlinear Schrodinger equation, waveguide dispersion, four-wave mixing, and the origin of optical nonlinearity.
  • Lab Demonstration 1: How we can measure a rainbow of light, even if we can’t see it with our eyes? We will measure the spectrum of various light sources using an optical spectrum analyzer.
  • Demonstration 2: Generating a new color of light using a photonic chip using a single-colored laser. We will use four-wave mixing to generate a new frequency (color) of light at a wavelength that satisfies the phase-matching condition, described in the introduction.
  • Demonstration 3: Generating a rainbow of colors from the same chip when we include more colors at the input. We will generate a supercontinuum using a nonlinear optical waveguide and a mode-locked laser as the input light source.

Hvilke faciliteter kommer du til at bruge?

You will get a tour of the High Speed Optical Communications Laboratory, where we have demonstrated several high-profile communications experiments.

You will also see the NanoLab cleanroom – the place where the devices are fabricated – from the outside looking in.

Tilmeldingen til SRP-øvelser 2023 er lukket

You can use the data from the demonstrations in the following ways

Demonstration 2 (Four-wave Mixing):

  • Calculate the bandwidth (range of frequencies) over which the wavelength-conversion process is most efficient
  • Determine the nonlinear coefficient and nonlinear index of the device used

Demonstration 3 (Supercontinuum Generation):

  • Use the collected data to calculate the dispersion of the waveguide
  • Verify the estimate of the nonlinear coefficient calculated from the data from Demonstration 2.

In the morning, we will go over the theoretical basis for what we will observe in the lab.

You will then get a tour of the lab before stopping for lunch.

In the afternoon, we will go through the demonstrations.

We will then go through the collected data, and you will have the opportunity to ask any questions about the demonstrations.

You will bring home data collected in the experiment, namely, files containing the measured light spectra under different conditions for different devices.

You will be able to visualize the data an interactive digital notebook using open-source software.

Forslag til litteratur, du kan bruge i din opgave og som baggrund for øvelsen:

  1. (background material): Wikipedia, “Four-Wave Mixing.” 
  2. (background material): Wikipedia, “Supercontinuum.” 
  3. (as a source of inspiration): Searching for Exoplanets Using a Microresonator Astrocomb 

NB: Når du har tilmeldt dig, vil du få besked, hvis der er litteratur, du skal læse som forberedelse til øvelsen.

  • Fysik:  the demonstrations will feature physics topics such as optics and materials science.
  • Matematik: mathematical models will be used to explain the demonstrations and to analyze the results. The student should have a strong interest in mathematics and open to learning new concepts.

Kan kombineres med:

  • Biologi
  • Optics
  • Four-wave mixing
  • Integrated photonics
  • Silicon photonics
  • Supercontinuum generation
  • Wavelength-division multiplexing

Tidspunkt og varighed

  • 1 .februar kl. 9-17

Antal deltagere


Opfølgende møde

- hvor du kan du få hjælp til  din databehandling og stille spørgsmål:

  • 8. februar kl. 13-15
  • 15. februar kl. 13-15



Arrangør og adresse

DTU Electro
Lyngby Campus


Kyv Kyvsgaard

Kyv Kyvsgaard Kommunikation og Outreach Institut for Elektroteknologi og Fotonik