openfermion.linalg.boson_ladder_sparse

Make a matrix representation of a singular bosonic ladder operator in the Fock space.

openfermion.linalg.boson_ladder_sparse(
    n_modes, mode, ladder_type, trunc
)

Since the bosonic operator lies in an infinite Fock space, a truncation value needs to be provide so that a sparse matrix of finite size can be returned.

n_modes int

Number of modes in the system Hilbert space.

mode int

The mode the ladder operator targets.

ladder_type int

This is a nonzero integer. 0 indicates a lowering operator, 1 a raising operator.

trunc int

The size at which the Fock space should be truncated when returning the matrix representing the ladder operator.

The corresponding trunc x trunc Scipy sparse matrix.