Bosonic Fractionalisation Transitions

TL;DR

This paper explores phase transitions between different charge sourcing mechanisms in holographic systems, demonstrating how bosonic solutions can break or preserve a global U(1) symmetry and connecting these phases within M-theory.

Contribution

It introduces a minimal model showing phase transitions between bulk matter sourced charge and horizon charge, and embeds these in M-theory with a connection to Schrödinger phases.

Findings

Identified phase transitions between explicit matter and horizon charge sources.

Embedded solutions in M-theory linking cohesive and neutral Schrödinger phases.

Demonstrated influence of relevant operators on phase structure.

Abstract

At finite density, charge in holographic systems can be sourced either by explicit matter sources in the bulk or by bulk horizons. In this paper we find bosonic solutions of both types, breaking a global U(1) symmetry in the former case and leaving it unbroken in the latter. Using a minimal bottom-up model we exhibit phase transitions between the two cases, under the influence of a relevant operator in the dual field theory. We also embed solutions and transitions of this type in M-theory, where, holding the theory at constant chemical potential, the cohesive phase is connected to a neutral phase of Schr\"odinger type via a z=2 QCP.