Bilayer manganites reveal polarons in the midst of a metallic breakdown
ORAL
Abstract
Just what tips the balance between the wealth of competing phases and textures in spin, charge and orbital degrees of freedom in the CMR manganites such as La$_{2-2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$ (LSMO)? Combining ARPES and STM/S measurements on bilayered LSMO (0.30$\le $x$<$0.5), we arrive at a compelling explanation for the seemingly contradictory data on the electronic structure of bilayered LSMO that has appeared in the literature. We show that the true signature of bilayered (N=2) LSMO is that of a gapped non-metal on the verge of a metallic breakdown. All the former confusion stems from the intrinsic presence of stacking faults leading to either more gapped single layer (N=1) LSMO or sharply peaked, N$>$2 slabs displaying true metallic double-exchange.
*This work is part of the research program of the Foundation for Fundamental Research on Matter (FOM), which is part of the Netherlands Organisation for Scientific Research (NWO).
–
Authors
F. Massee
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
S. de Jong
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
Y. Huang
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
W. K. Siu
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
I. Santoso
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
A. Mans
Van der Waals-Zeeman Institute, University of Amsterdam, 1018XE Amsterdam, The Netherlands
A. T. Boothroyd
Clarendon Laboratory, Oxford University, OX1 3PU Oxford, UK
D. Prabhakaran
Clarendon Laboratory, Oxford University, OX1 3PU Oxford, UK
