ffsim.s_plus_operator¶
- ffsim.s_plus_operator(norb)[source]¶
Spin raising operator.
The spin raising operator is defined as
\[S_+ = \sum_{i=0}^{N-1} a^\dagger_{i\alpha} a_{i\beta}\]where \(N\) is the number of spatial orbitals.
- Parameters:
norb (
int) – The number of spatial orbitals.- Return type:
- Returns:
The spin raising operator.