Why magnetic monopole becomes dyon in topological insulators

Autor:	Aoki, Shoto, Fukaya, Hidenori, Kan, Naoto, Koshino, Mikito, Matsuki, Yoshiyuki
Rok vydání:	2023
Předmět:	Condensed Matter - Mesoscale and Nanoscale Physics Condensed Matter - Strongly Correlated Electrons High Energy Physics - Lattice High Energy Physics - Theory
Druh dokumentu:	Working Paper
Popis:	The Witten effect predicts that a magnetic monopole acquires a fractional electric charge inside topological insulators. In this work, we give a microscopic description of this phenomenon, as well as an analogous two-dimensional system with a vortex. We solve the Dirac equation of electron field both analytically in continuum and numerically on a lattice, by adding the Wilson term and smearing the gauge field within a finite range to regularize the short-distance behavior of the system. Our results reveal that the Wilson term induces a strong positive mass shift, creating a domain-wall around the monopole/vortex. This small, yet finite-sized domain-wall localizes the chiral zero modes and ensures their stability through the Atiyah-Singer index theorem, whose cobordism invariance is crucial in explaining why the electric charge is fractional. Comment: 40 pages, 10 figures, minor corrections, references added, published version
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2304.13954 Zobrazit plný text záznamu View this record from Arxiv