"Could it be the same principles that make a faraday cage work?"
Perhaps, in the very general sense that Maxwell's equations and charge conductors are involved. Since this is a quantum system only two atoms thick, the detailed explanation is going to end up being a bit different from any classical model. I'm sure they have some ideas, but I haven't seen the original article yet, so I can't comment on that.
And as for "order of magnitude," in physical science, so far as I've ever encountered (being a professional in the field), it invariably means a factor of ten. If it occasionally means something different to computer scientists, then this is a cultural difference that I (and I expect many other scientists) have never encountered.
In practice, when you say "an order of magnitude," you mean "about a factor of 10." It might be 8 or it might be 11, and this is commonly understood among physical scientists. But when you say "a factor of 10" and it's 8, then people could accuse you of dishonesty. So the two phrases don't mean quite the same thing. One is more precise than the other.