73 citations · 133 across the 6 of their papers we have counts for
8 papers
Mott transition in lattice boson models
Roberto Fernandez, Juerg Froehlich, Daniel Ueltschi
We use mathematically rigorous perturbation theory to study the transition between the Mott insulator and the conjectured Bose-Einstein condensate in a hard-core Bose-Hubbard model…
Statistical Mechanics of Thermodynamic Processes
Jürg Fröhlich, Marco Merkli, Simon Schwarz +1
In this note we describe some results concerning non-relativistic quantum systems at positive temperature and density confined to macroscopically large regions of physical space wh…
Hund's rule and metallic ferromagnetism
Juerg Froehlich, Daniel Ueltschi
We study tight-binding models of itinerant electrons in two different bands, with effective on-site interactions expressing Coulomb repulsion and Hund's rule. We prove that, for su…
Segregation in the asymmetric Hubbard model
Daniel Ueltschi
We study the `asymmetric' Hubbard model, where hoppings of electrons depend on their spin. For strong interactions and sufficiently asymmetric hoppings, it is proved that the groun…
Cluster expansions and correlation functions
Daniel Ueltschi
A cluster expansion is proposed, that applies to both continuous and discrete systems. The assumption for its convergence involves an extension of the neat Kotecky-Preiss criterion…
Dissipative Transport: Thermal Contacts and Tunnelling Junctions
Juerg Froehlich, Marco Merkli, Daniel Ueltschi
The general theory of simple transport processes between quantum mechanical reservoirs is reviewed and extended. We focus on thermoelectric phenomena, involving exchange of energy…