Zhang-Rice singlet excitation around 2 eV is observed, distinguished from Cu dd excitations, by a symmetry selective resonant soft x-ray Raman scattering (RSXRS) experiments at the O 1s edge excitation of Sr2CuO2Cl2. Well below Néel temperature the initial state of Sr2CuO2Cl2 is antiferromagnetic, and then the final state with the Zhang-Rice singlet is excited selectively when the photon polarization is conserved in the RSXRS process. We also observe a weak RSXRS structures around 0.5 eV in the controversial midinfrared region, taking advantage of extremely weak elastic scattering intensity in the O 1s edge. From its polarization dependence, it is interpreted to originate mainly from the two-spin-flip excitations.
|Number of pages||5|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Oct 15 2002|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics