Nonuniform Parafermion Chains: Low-Energy Physics and Finite-Size Effects

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Fatmehsari, Mohammad Mahdi Nasiri, Vaezi, Mohammad-Sadegh
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918012456534016
author Fatmehsari, Mohammad Mahdi Nasiri
Vaezi, Mohammad-Sadegh
author_facet Fatmehsari, Mohammad Mahdi Nasiri
Vaezi, Mohammad-Sadegh
contents The nonuniform $\mathbb{Z}_2$ symmetric Kitaev chain, comprising alternating topological and normal regions, hosts localized states known as edge-zero modes (EZMs) at its interfaces. These EZMs can pair to form qubits that are resilient to quantum decoherence, a feature expected to extend to higher symmetric chains, i.e., parafermion chains. However, finite-size effects may impact this ideal picture. Diagnosing these effects requires first a thorough understanding of the low-energy physics where EZMs may emerge. Previous studies have largely focused on uniform chains, with nonuniform cases inferred from these results. While recent work [Narozhny, Sci. Rep. 7, 1447 (2017)] provides an insightful analytical solution for a nonuniform $\mathbb{Z}_2$ chain with two topological regions separated by a normal one, its complexity limits its applicability to chains with more regions or higher symmetries. Here, we present a new approach based on decimating the highest-energy terms, facilitating the scalable analysis of $\mathbb{Z}_n$ chains with any number of regions. We provide analytical results for both $\mathbb{Z}_2$ and$\mathbb{Z}_3$ chains, supported by numerical findings, and identify the critical lengths necessary to preserve well-separated EZMs.
format Preprint
id arxiv_https___arxiv_org_abs_2412_03793
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Nonuniform Parafermion Chains: Low-Energy Physics and Finite-Size Effects
Fatmehsari, Mohammad Mahdi Nasiri
Vaezi, Mohammad-Sadegh
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Statistical Mechanics
Superconductivity
Quantum Physics
The nonuniform $\mathbb{Z}_2$ symmetric Kitaev chain, comprising alternating topological and normal regions, hosts localized states known as edge-zero modes (EZMs) at its interfaces. These EZMs can pair to form qubits that are resilient to quantum decoherence, a feature expected to extend to higher symmetric chains, i.e., parafermion chains. However, finite-size effects may impact this ideal picture. Diagnosing these effects requires first a thorough understanding of the low-energy physics where EZMs may emerge. Previous studies have largely focused on uniform chains, with nonuniform cases inferred from these results. While recent work [Narozhny, Sci. Rep. 7, 1447 (2017)] provides an insightful analytical solution for a nonuniform $\mathbb{Z}_2$ chain with two topological regions separated by a normal one, its complexity limits its applicability to chains with more regions or higher symmetries. Here, we present a new approach based on decimating the highest-energy terms, facilitating the scalable analysis of $\mathbb{Z}_n$ chains with any number of regions. We provide analytical results for both $\mathbb{Z}_2$ and$\mathbb{Z}_3$ chains, supported by numerical findings, and identify the critical lengths necessary to preserve well-separated EZMs.
title Nonuniform Parafermion Chains: Low-Energy Physics and Finite-Size Effects
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Statistical Mechanics
Superconductivity
Quantum Physics
url https://arxiv.org/abs/2412.03793