The formation of a wave-like interference pattern when photons, electrons or other particles pass through two narrow slits and impinge on a screen or detector on the other side is the ultimate demonstration of quantum reality: individual particles behaving like waves.
This experiment, Young’s interference experiment, also referred to as Young’s double-slit experiment works with electrons, neutrons, atoms and even molecules. The odd thing is that classical physics cannot explain what happens. How do the individual particles passing through one or other of the slits “know”, what the particles that went before did?
We mentioned the latest example of the Young’s slits experiment on Chemspy earlier this week as Markus Arndt and colleagues have used nanofabrication and nano-imaging to record in real-time a video of the build-up of a quantum interference pattern from fluorescent dye molecules, known as phthalocyanines. One thing lacking from the various news reports was a video, so I asked Arndt to point readers to a suitable resource. Here’s the result: http://youtu.be/vCiOMQIRU7I
Higher resolution version and more information can be found on the team’s site here.