API Reference

The PairInteraction package provides a Python interface for easily accessing the functionality in a pythonic way. This Python interface can be accessed via the pairinteraction module by importing

import pairinteraction as pi

Alternatively, the same functionality can be accessed using real data types via import pairinteraction.real as pi which can accelerate the calculations if no complex numbers are needed (i.e. no fields in y-direction). The classes and functionality in both cases are identical, only the data type used internally differs.

All the available classes, methods and functions for pairinteraction (as well as for pairinteraction.real) are documented below:

Database

Database

Class for handling the databases for the PairInteraction package.

Single Atom

KetAtom

Ket for an atomic basis state.

StateAtom

State of a single atom.

BasisAtom

Basis for a single atom.

SystemAtom

System of a single atom.

Pair of Atoms

KetPair

Ket for a pair state of two atoms.

StatePair

Pair state of two atoms.

BasisPair

Basis for a pair of atoms.

SystemPair

System of a pair of atoms.

GreenTensor

Green tensor for the multipole pair interactions.

Convenience Functions

diagonalize(systems[, diagonalizer, ...])

Diagonalize a list of systems in parallel using the C++ backend.

Perturbative Calculations

EffectiveSystemPair

Class for creating an effective SystemPair object and calculating the effective Hamiltonian.

C3

Class for calculating the C3 coefficient between two states.

C6

Class for calculating the C6 coefficient for a two-atom state |ket1, ket2>.