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A local metallic state in globally insulating $La_{1.24}Sr_{1.76}Mn_2O_7$ well above the metal-insulator transition

Z. Sun·J. F. Douglas·A. V. Fedorov·Y. -D. Chuang·H. Zheng·J. F. Mitchell·D. S. Dessau
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Abstract

Angle-resolved photoemission spectroscopy was used to investigate the evolution of the electronic structure across the metal-insulator transition in bi-layer manganite $La_{1.24}Sr_{1.76}Mn_2O_7$. We found that this system is a metal for $T T^*$. These results indicate the critical role of electronic phase separation and percolation effects for the metal-insulator transition in $La_{1.24}Sr_{1.76}Mn_2O_7$.

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Z. Sun, J. F. Douglas, A. V. Fedorov, Y. -D. Chuang, H. Zheng, J. F. Mitchell, D. S. Dessau. 2006-12-27. A local metallic state in globally insulating $La_{1.24}Sr_{1.76}Mn_2O_7$ well above the metal-insulator transition. https://doi.org/10.1038/nphys517

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