The hole concentration dependence of the magnetic correlations is studied in very lightly-doped La2−xSrxCuO4 (x<0.02), which shows coexistence of a three-dimensional antiferromagnetic (AF) long-range ordered phase and a spin-glass phase at low temperatures. It is found that the spin-glass phase in the coexistence region also shows a diagonal spin modulation as in the pure spin-glass phase in La2−xSrxCuO4 (0.02≤x≤0.055). Below x∼0.02 the diagonal stripe structure is the same as that in x∼0.02 with a volume fraction almost proportional to hole concentration, suggesting that electronic phase separation of the doped holes occurs so that some regions with hole concentration hc∼0.02 and the rest with hc∼0 are formed. This result also indicates that the transition between the AF and spin-glass phase around x=0.02 is first order.
@article{arxiv.cond-mat/0111228,
title = {Electronic phase separation in lightly-doped La$_{2-x}$Sr$_x$CuO$_4$},
author = {M. Matsuda and M. Fujita and K. Yamada and R. J. Birgeneau and Y. Endoh and G. Shirane},
journal= {arXiv preprint arXiv:cond-mat/0111228},
year = {2009}
}