Growing quantum states with topological order

TL;DR

This paper presents a protocol for growing topologically ordered quantum states in many-body systems through flux and particle insertion, analyzing its effectiveness across small and large systems.

Contribution

It introduces a novel protocol for creating topological states and develops an effective composite fermion model to study large systems with topological order.

Findings

Fidelity of state growth scales with particle number N.

Effective composite fermion model captures effects of dispersive bands and edges.

Protocol successfully applied to fractional quantum Hall systems.

Abstract

We discuss a protocol for growing states with topological order in interacting many-body systems using a sequence of flux quanta and particle insertion. We first consider a simple toy model, the superlattice Bose Hubbard model, to explain all required ingredients. Our protocol is then applied to fractional quantum Hall systems in both, continuum and lattice. We investigate in particular how the fidelity, with which a topologically ordered state can be grown, scales with increasing particle number N. For small systems exact diagonalization methods are used. To treat large systems with many particles, we introduce an effective model based on the composite fermion description of the fractional quantum Hall effect. This model also allows to take into account the effects of dispersive bands and edges in the system, which will be discussed in detail.