2017/05/31 by Nitin Chelwani, N. Chelwani, Andreas Baum +13
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Amplitude #Antiferromagnetism #Condensed matter physics #Cuprate #Energy (signal processing) #Excitation #Iron-based superconductors research #Magnetic field #Magnetization #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Scattering #Spectral line #Superconductivity #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.97.024407
published as Phys. Rev. B 97, 024407 (2018) · 8 pages, 7 figures
openalex publication_date 2018/01/09 · arxiv created 2018/05/05 · arxiv updated 2018/05/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present results from light scattering experiments on three insulating antiferromagnetic cuprates, YBa2Cu3O6.05, Bi2Sr2YCu2O_8+\ensuremathδ, and La2CuO4 as a function of polarization and excitation energy using samples of the latest generation. From the raw data we derive symmetry-resolved spectra. The spectral shape in B1g symmetry is found to be nearly universal and independent of excitation energy. The spectra agree quantitatively with predictions by field theory [Eur. Phys. J. B 88, 237 (2015)] facilitating the precise extraction of the Heisenberg coupling J. In addition, the asymmetric lineshape on the high-energy side is found to be related to amplitude fluctuations of the magnetization. In La2CuO4 alone, minor contributions from resonance effects may be identified. The spectra in the other symmetries are not universal. The variations may be traced back to weak resonance effects and extrinsic contributions. For all three compounds we find support for the existence of chiral excitations appearing as a continuum in A2g symmetry having an onset slightly below 3J. In La2CuO4 an additional isolated excitation appears on top of the A2g continuum.