2023/11/27 by Y. del Castillo, J. Fernández‐Rossier, del Castillo, Y. +1
Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Quantum Physics (quant-ph) #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.2311.15720
openalex publication_date 2023/11/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The emergence of effective S=1/2 spins at the edges of S=1 Haldane spin chains is one of the simplest examples of fractionalization. Whereas there is indirect evidence of this phenomenon, direct measurement of the magnetic moment of an individual edge spin remains to be done. Here we show how scanning tunnel microscopy electron-spin resonance (ESR-STM) can be used to map the stray field created by the fractional S=1/2 edge spin and we propose efficient methods to invert the Biot-Savart equation, obtaining the edge magnetization map. This permits one to determine unambiguously the two outstanding emergent properties of fractional degrees of freedom, namely, their fractional magnetic moment and their localization length ξ.