Suppression of charge stripes in highly strained, epitaxial La$_{5/3}$Sr$_{1/3}$NiO$_{4}$ films

We have successfully grown epitaxial La$_{5/3}$Sr$_{1/3}$NiO$_{4}$ films with a small crystalline mosaic using pulsed laser deposition. Using synchrotron radiation, the x-ray diffraction peaks associated with charge stripes have been successfully observed for relatively thick films with little strain. Anomalies due to the charge-ordering transition have been examined using four-point probe resistivity measurement. We also have produced highly strained films with the same total thickness through the use of multilayers of La$_{5/3}$Sr$_{1/3}$NiO$_{4}$ alternating with SrTiO$_{3}$. These films remain under in-plane tension. A thorough search for the charge stripe peaks in the strained multilayers has been negative; the stripes appear to be suppressed under these conditions. This suggests that electron-lattice interactions are critical for the formation of stripe phases. This work is supported through NSF DMR-0239667. Some data was taken at the National Synchrotron Light Source, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Division of Materials Sciences and Division of Chemical Sciences.