"Reentrant insulating state in ultrathin manganite films"

Bongju Kim: Daeyoung Kwon, Takeaki Yajima, Christopher Bell, Yasuyuki Hikita, Bog G. Kim, and Harold Y. Hwang; Appl. Phys. Lett., 09/02/11.

Additional Authors: Daeyoung Kwon, Takeaki Yajima, Christopher Bell, Yasuyuki Hikita, Bog G. Kim, and Harold Y. Hwang

Abstract:

The transport and magnetic properties of La0.7Sr0.3MnO3 thin-films grown by pulsed laser deposition on (LaAlO3)0.3(SrAl0.5Ta0.5O3)0.7 single crystal substrates have been investigated. A systematic series with various thicknesses of La0.7Sr0.3MnO3 was used to establish a phase diagram which showed a clear difference compared to films grown on SrTiO3 substrates, highlighting the importance of film thickness, and substrate strain. At 8 unit cells, the boundary between the metallic and insulating groundstates, a second abrupt metal-insulator transition was observed at low temperatures, which could be tuned by magnetic field, and was interpreted as a signature of electronic phase separation.