lattice-symmetries: A package for working with quantum many-body bases

Abstract

Exact diagonalization (ED) is one of the most reliable and established numerical methods of quantum many-body theory. It is precise, unbiased, and general enough to be applicable to a huge variety of problems in condensed matter physics. Mathematically, ED is a linear algebra problem involving a matrix called the Hamiltonian. For a system of spin-1/2 particles, the size of this matrix scales exponentially (as O(2 N )) with the number of particles N .