Linear Canonical-Ensemble Quantum Monte Carlo: From Dilute Fermi Gas to Flat-Band Ferromagnetism
We present a finite-temperature canonical-ensemble determinant quantum Monte Carlo algorithm that enforces an exact fermion number and enables stable simulations of correlated lattice fermions. We propose a stabilized QR update that reduces the computational complexity from standard cubic scaling $O(βN^3)$ to linear scaling $O(βN...