This surreal, beautiful short movie looks like gooey light effects at a dance party, but it actually demonstrates how nanocrystals work. The brilliant colors in you see in the liquid are actually millions of tiny crystals emitting light.
These nanocrystals come in the form of quantum dots, which are ultratiny clusters of crystals made of semiconductors.
When the dots are illuminated with an argon laser, they absorb light and then radiate it back out. The smaller the dot is, the higher the frequency at which it radiates. So a bigger dot would be toward the red end of the spectrum, and a smaller one would be toward the blue end. Each container of liquid radiates in a different color depending on the quantum dots floating in the solution inside. (The tiny flecks of blue that you're seeing are bits of dust - the dots themselves are microscopic.)
Nanocrystals have a number of real-world applications: They're used in everything from solar cells and oil filters to cutting-edge medical imaging technology.
This video, called "3 Nano," was created last year by Dean W. Armstrong. He writes:
This video was compiled from fluorescing colloidal quantum dots of different sizes excited by an argon laser. The dots are invisible (with one exception in a microscope at 2:14) but they produce the bright colors in the beam. The bits of bright blue flashes are dust particles in the solutions.
The music is from Ms. John Soda, the song is "Technicolor" from the album No P. or D.