I'm doing research to interpret quantum physics in terms of the concept "matter is information". I'm trying to understand what is information.

I like the explanation in https://physics.stackexchange.com/q/2689 (including what is commented by Noldorin and Anixx). Could someone suggest me the book/papers which expand that? I seek both the mathematics and the intuition behind.

I have skimmed a couple of quantum information books. They seem to be useless overkill for the moment.