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arXiv · 2601.19505

Rimu.jl: Random integrators for many-body quantum systems

Matija Čufar·C. J. Bradly·Ray Yang·Elke Pahl·Joachim Brand
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Abstract

Rimu$.$jl is a Julia package for solving many-body quantum problems. The core of the package is a matrix-free implementation of Hamiltonians and other operators and compact representation of Fock states, which together allow for efficient methods suitable for high-performance computing. Rimu$.$jl includes a Julia implementation of the full configuration interaction quantum Monte Carlo (FCIQMC) algorithm which is a type of projector QMC algorithm for stochastically solving the time-independent Schr\"odinger equation. It also includes many well-known model Hamiltonians, and an interface for exact diagonalisation based on external eigenvalue solvers. Both the stochastic and exact diagonalisation methods are accessed with a CommonSolve$.$jl interface. We describe the FCIQMC algorithm and how to obtain estimators of observables as well as the key features of the implementation.

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Matija Čufar, C. J. Bradly, Ray Yang, Elke Pahl, Joachim Brand. 2026-01-27. Rimu.jl: Random integrators for many-body quantum systems. https://arxiv.org/abs/2601.19505

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