Fractional Spin Excitations in the Infinite-Layer Cuprate CaCuO2
Artikel i vetenskaplig tidskrift, 2022

We use resonant inelastic x-ray scattering (RIXS) to investigate the magnetic dynamics of the infinite-layer cuprate CaCuO2. We find that close to the (1/2,0) point, the single magnon decays into a broad continuum of excitations accounting for about 80% of the total magnetic spectral weight. Polarization-resolved RIXS spectra reveal the overwhelming dominance of the spin-flip (Delta S = 1) character of this continuum with respect to the Delta S = 0 multimagnon contributions. Moreover, its incident-energy dependence is identical to that of the magnon, supporting a common physical origin. We propose that the continuum originates from the decay of the magnon into spinon pairs, and we relate it to the exceptionally high ring exchange J(c) similar to J(1) of CaCuO2. In the infinite-layer cuprates, long-range and multisite hopping integrals are very important, and they amplify the 2D quantum magnetism effects in spite of the 3D antiferromagnetic Neel order.

Författare

Leonardo Martinelli

Politecnico di Milano

Davide Betto

European Synchrotron Radiation Facility (ESRF)

Kurt Kummer

European Synchrotron Radiation Facility (ESRF)

Riccardo Arpaia

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Lucio Braicovich

Politecnico di Milano

European Synchrotron Radiation Facility (ESRF)

Daniele Di Castro

Universita degli Studi di Roma Tor Vergata

Nicholas B. Brookes

European Synchrotron Radiation Facility (ESRF)

Marco Moretti Sala

Politecnico di Milano

Giacomo Ghiringhelli

Politecnico di Milano

Physical Review X

21603308 (eISSN)

Vol. 12 2 021041

Resonant inelastisk röntgenspridning för att studera förändringar i högtemperatursupraledares fasdiagram orsakade av mekanisk påfrestning och inneslutning

Vetenskapsrådet (VR) (2020-04945), 2021-01-01 -- 2024-12-31.

Ämneskategorier

Atom- och molekylfysik och optik

Annan fysik

Den kondenserade materiens fysik

DOI

10.1103/PhysRevX.12.021041

Mer information

Senast uppdaterat

2023-01-10