%0 Journal Article
%T Optimization of finite-size errors in finite-temperature calculations of unordered phases
%A Deepak Iyer
%A Mark Srednicki
%A Marcos Rigol
%J Physics
%D 2015
%I arXiv
%R 10.1103/PhysRevE.91.062142
%X It is common knowledge that the microcanonical, canonical, and grand-canonical ensembles are equivalent in thermodynamically large systems. Here, we study finite-size effects in the latter two ensembles. We show that contrary to naive expectations, finite-size errors are exponentially small in grand canonical ensemble calculations of translationally invariant systems in unordered phases at finite temperature. Open boundary conditions and canonical ensemble calculations suffer from finite-size errors that are only polynomially small in the system size. We further show that finite-size effects are generally smallest in numerical linked cluster expansions. Our conclusions are supported by analytical and numerical analyses of classical and quantum systems.
%U http://arxiv.org/abs/1505.03620v2