Charge superstructures in Zn-doped La$_{2-x}$Sr$_x$CuO$_4$
ORAL
Abstract
We have observed valence band charge order in both twinned and untwinned samples of La$_{1.95}$Sr$_{0.05}$Cu$_{0.95}$Zn$_{0.05} $O$_{4}$ with resonant soft x-ray scattering. In the untwinned sample the order was observed to be mainly electronic and centered at the (0,0.084,2)$_o$ position in reciprocal space, indicating diagonal charge order with period $12 a_o$, where $a_o$ is the orthorhombic lattice parameter. This order has approximately half the wavelength of the magnetic order previsouly observed with neutron scattering* in this system, suggesting a stripe interpretation. Preliminary measurements on a twinned sample revealed four satellites at (0,$K$,2)$_o$, where $K$ takes on integer multiples of the value 0.011. Relationships between these effects and the crystal structure of La$_{1.95}$Sr$_{0.05}$Cu$_{0.95}$Zn$_{0.05}$O$_{4}$ will be discussed. *M. Matsuda, et. al., Phys. Rev. B {\bf 73}, 140503(R) (2006)
*Funded by US DOE grant DE-FG02-06ER46285 and Helmholtz Assn. contract VH-FZ-007
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