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arXiv · 2310.16091

Long-range entanglement and topological excitations

Gianpaolo Torre·Jovan Odavić·Pierre Fromholz·Salvatore Marco Giampaolo·Fabio Franchini
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Abstract

Topological order comes in different forms, and its classification and detection is an important field of modern research. In this work, we show that the Disconnected Entanglement Entropy, a measure originally introduced to identify topological phases, is also able to unveil the long-range entanglement (LRE) carried by a single, fractionalized excitation. We show this by considering a quantum, delocalized domain wall excitation that can be introduced into a system by inducing topological frustration in an antiferromagnetic spin chain. Furthermore, we study the resilience of LRE against a quantum quench and the introduction of disorder, thus establishing the existence of a phase with topological features despite not being a typical topological order or symmetry-protected one.

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Gianpaolo Torre, Jovan Odavić, Pierre Fromholz, Salvatore Marco Giampaolo, Fabio Franchini. 2023-10-24. Long-range entanglement and topological excitations. https://doi.org/10.21468/scipostphyscore.7.3.050

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