====== Qxy ======
###
The xy component of $Q$ is defined as:
\begin{equation}
Q_{xy} = 3xy/r^2.
\end{equation}
The equivalent operator in Quanty is created by:
OppQxy = NewOperator("Qxy", NF, IndexUp, IndexDn)
The operator could also be defined by:
Akm={{2,-2,sqrt(1.5)*I},{2, 2,-sqrt(1.5)*I}}
OppQxy=NewOperator("CF",NF,indexup,indexdn,Akm)
###
===== Table of contents =====
{{indexmenu>.#1}}