Some time I am so picky, I hate myself! :)
This has all the good intentions, but the visual picture it has given is not correct. A student is attempting to demonstrate a "potential barrier" that we often have to deal with in a quantum mechanics class. She does this by creating a "snow sculpture" that consists of a wall of snow. But to show that an electron an tunnel through the barrier, she created a hole in the wall!
So the question is, is this a valid and accurate-enough visual representation of the phenomenon?
I claim that it is not. When I used to do point-contact tunneling, we pushed the tip onto the insulating barrier until we see a tunneling current. However, depending on how fragile the insulating barrier is, or how much force you push with the tip, sometime the barrier cracks and forms pinholes. These pinholes will then create Ohmic contacts and basically a short, where the current flow is the normal conduction. You no longer see tunneling current.
So when I look at the video in this demonstration, I can't help but see this hole in the barrier as not an illustration of electron tunneling, but rather, an Ohmic contact.
Oh well, I really should stop picking on students like this! :)