



01616nas a2200133   4500008004100000245009200041210006900133260001500202490000600217520117300223100002801396700001901424856003901443       2022                        eng d00aHow to build Hamiltonians that transport noncommuting charges in quantum thermodynamics0 aHow to build Hamiltonians that transport noncommuting charges in  c01/27/20220 v83 a<p>Noncommuting conserved quantities have recently launched a subfield of quantum thermodynamics. In conventional thermodynamics, a system of interest and a bath exchange quantities -- energy, particles, electric charge, etc. -- that are globally conserved and are represented by Hermitian operators. These operators were implicitly assumed to commute with each other, until a few years ago. Freeing the operators to fail to commute has enabled many theoretical discoveries -- about reference frames, entropy production, resource-theory models, etc. Little work has bridged these results from abstract theory to experimental reality. This paper provides a methodology for building this bridge systematically: We present an algorithm for constructing Hamiltonians that conserve noncommuting quantities globally while transporting the quantities locally. The Hamiltonians can couple arbitrarily many subsystems together and can be integrable or nonintegrable. Special cases of our construction have appeared in quantum chromodynamics (QCD). Our Hamiltonians may be realized physically with superconducting qudits, with ultracold atoms, with trapped ions, and in QCD.</p>1 aHalpern, Nicole, Yunger1 aMajidy, Shayan  uhttps://arxiv.org/abs/2103.14041v1