Examples
The rules for maximas simplifier can be found in "ladder.mac". Load the code
with
load("ladder.amc");
to tell maxima how to handle these operators. A nearly complete description
what the code does and why is given in this pdf file:
Rule-based simplification of ladder operators with Maxima
Theoretical background
Theoretical background on the ladder operators can be found in any quantum physics textbook.
Another primary source of information is the english wikipedia page:
Creation and annihilation operators