1998/12/02 by Y. Lin, Yufeng Lin, J. Sichelschmidt +9
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con) #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/9812027
6 pages, 4 eps figures, submitted to PRB
arxiv created 1998/12/02 · openalex publication_date 1998/12/02 · arxiv updated 2016/08/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We reported two-magnon Raman scattering from La1.9Sr0.1CuO4, which has a suppressed Tc=12 K, as the temperature is lowered below 37 K and an ordered spin phase is formed. The two-magnon Raman intensity increases with decreasing temperature. The magnetic scattering in La1.9Sr0.1CuO4 is totally different from that reported in the parent compound La2CuO4. We analyze the line shape of the two-magnon scattering within the traditional Loudon-Fleury theory and find the superexchange constant J=1052 cm-1. The calculation of the frequency moment suggests that the quantum fluctuations are very weak in the system. The room temperature Raman scattering from La2CuO4 is also measured. Strong features appear in the one-phonon spectrum at the frequencies of the longitudinal optical (LO) infrared modes which we suggest become Raman active through a Fröhlich-interaction.