Two-magnon Raman scattering in (La 1-x Sr x ) 2 CuO 4

摘要: The two-dimensional two-magnon peak in (${\mathrm{La}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Sr}}_{\mathrm{x}}$${)}_{2}$${\mathrm{CuO}}_{4}$ decreases rapidly from x=0 to x=0.01. For xg0.03 scattering is observed over a very wide energy region low 4000 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. This indicates that the correlation length of spin order decrease can be related rapid three-dimensional antiferromagnetic transition temperature (${T}_{N}$), while at still retains short and time. At xl0.01 resonant state with narrow electronic levels which about 18 000 narrowness these levels, simultaneous extinction resonance scattering, suggest are localized relating Cu spins.