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arXiv · 1909.12105

Effects of energy extensivity on the quantum phases of long-range interacting systems

Thomas Botzung·David Hagenmüller·Guido Masella·Jérôme Dubail·Nicolò Defenu·Andrea Trombettoni·Guido Pupillo
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Abstract

We investigate the ground state properties of one-dimensional hard-core bosons interacting via a variable long-range potential using the density matrix renormalization group. We demonstrate that restoring energy extensivity in the system, which is done by rescaling the interaction potential with a suitable size-dependent factor known as Kac's prescription, has a profound influence on the low-energy properties in the thermodynamic limit. While an insulating phase is found in the absence of Kac's rescaling, the latter leads to a new metallic phase that does not fall into the conventional Luttinger liquid paradigm. Our results in one dimension illustrate the subtlety of determining the thermodynamic properties of generic long-range quantum systems.

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Thomas Botzung, David Hagenmüller, Guido Masella, Jérôme Dubail, Nicolò Defenu, Andrea Trombettoni, Guido Pupillo. 2019-09-26. Effects of energy extensivity on the quantum phases of long-range interacting systems. https://doi.org/10.1103/physrevb.103.155139

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