MagneticKP: A package for quickly constructing k⋅p models of magnetic and non-magnetic crystals

We propose an efficient algorithm for constructing k⋅p effective Hamiltonians, which is much faster than previously proposed algorithms. This algorithm is implemented in MagneticKP package. The package applies to both single-valued (spinless) and double-valued (spinful) cases, and to both magnetic and nonmagnetic systems. By interfacing with SpaceGroupIrep or MSGCorep packages, it can directly output the k⋅p Hamiltonian around arbitrary momentum point and expanded to arbitrary order in k.