### Short-range Charge and Spin Superstructures in Doped Layered Co PerovskitesShort-range Charge and Spin Superstructures in Doped Layered Co Perovskites

Access Restriction
Open

 Author Sakiyama, N. ♦ Zaliznyak, I. A. ♦ Lee, S. -H ♦ Mitsui, Y. ♦ Yoshizawa, H. Source arXiv.org Content type Text File Format PDF Date of Submission 2008-07-31 Language English
 Subject Domain (in DDC) Computer science, information & general works ♦ Natural sciences & mathematics ♦ Physics Subject Keyword Condensed Matter - Strongly Correlated Electrons ♦ Condensed Matter - Materials Science ♦ physics:cond-mat Abstract We have investigated cobaltite relatives of the layered perovskite cuprates and nickelates, Pr$_{2-x}$Ca$_x$CoO$_4$ ($0.39 \leq x \leq 0.73$) and La$_{2-x}$Sr$_x$CoO$_4$ ($x = 0.61$), using elastic neutron scattering. We have discovered doping-dependent incommensurate short-range ordering of charges and magnetic moments, which in cobaltites occur in the range of heavy doping, $0.5 \lesssim x \lesssim 0.75$. The charge order exists already at room temperature and shows no change on cooling. The incommensurability of its propagation vector, ${\bf Q}_c = (\epsilon_c,0,l)$, roughly scales with the concentration of Co$^{2+}$ ions, $\epsilon_c \sim (1-x)$. Magnetic order is only established at low T$\lesssim 40$ K and has twice larger periodicity, indicating a dominant antiferromagnetic correlation between the nearest Co$^{2+}$ spins. Description Reference: Phys. Rev. B 78, 180406 (2008) Educational Use Research Learning Resource Type Article Page Count 4