Quantum Physics in Soviet Russia? (by Gruppa-L)

Quantum Physics in Soviet Russia?

So what is it with Quantum Physics and reflecting armbands?!

You have probably seen photos with Russian soldiers or special forces wearing reflecting armbands by Альфа Спецснаряжение already. They are usually worn for quicker identification in assaults or generally close quarter situations. That is why we bought a couple of those for our team.

The first thing that made us wonder was the price. 15$ for a tiny little yellow strap? Well, life’s a bitch.
But when we used them at while playing night the first time I immediately noticed that they seem to glow somehow – they were brighter then you think they should be. Most of the time you could not see anything, but the glowing armband of someone whizzing threw the night. And it is not that kind of glow where you have to charge it up light. It is just permanent bright.

Back at home I fiddled around with different light sources trying to find out what was going on with that thing. I noticed that only blue and UV light made it glow. You can see the effect pretty good on the photo below:

To put it in a nutshell: Blue light contains more energy per photon due to it’s wavelength then green one. The blue light is absorbed by the armband and green light emitted. But due to the energy difference between those two it can emit more green light then it absorbs blue light (in terms of photon count). This leads to the glowing effect. At night the stray light by the moon is enough to cause this effect.
How this happens in detail is pretty magic. The electrons use forbidden band gaps and violate a couple of physical laws. Though I am in my 9th semester of electronic engineering it was still somehow hard to understand.

Some more reference photos for you: