title: Electron Doping of the Parent Cuprate La_{2}CuO_{4} without Cation Substitution.
abstract: In the cuprates, carrier doping of the Mott insulating parent state is necessary to realize superconductivity as well as a number of other exotic states involving charge or spin density waves. Cation substitution is the primary method for doping carriers into these compounds, and is the only known method for electron doping in these materials. Here, we report electron doping without cation substitution in epitaxially stabilized thin films of La_{2}CuO_{4} grown via molecular-beam epitaxy. We use angle-resolved photoemission spectroscopy to directly measure their electronic structure and conclusively determine that these compounds are electron doped with a carrier concentration of 0.09±0.02 e^{-}/Cu. We propose that intrinsic defects, most likely oxygen vacancies, are the sources of doped electrons in these materials. Our results suggest a new approach to electron doping in the cuprates, one which could lead to a more detailed experimental understanding of their properties.
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Haofei I
authors.initials: HI
authors.lastname: Wei
authors.affiliation: Department of Applied Physics, Stanford University, Palo Alto, California 94306, USA.
authors.forename: Carolina
authors.initials: C
authors.lastname: Adamo
authors.affiliation: School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Nowadnick
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Edward B
authors.initials: EB
authors.lastname: Lochocki
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Shouvik
authors.initials: S
authors.lastname: Chatterjee
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Jacob P
authors.initials: JP
authors.lastname: Ruf
authors.affiliation: Department of Applied Physics, Stanford University, Palo Alto, California 94306, USA.
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Beasley
authors.affiliation: Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors.forename: Darrell G
authors.initials: DG
authors.lastname: Schlom
authors.affiliation: Laboratory of Atomic and Solid State Physics, Department of Physics, Cornell University, Ithaca, New York 14853, USA.|Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, USA.
authors.forename: Kyle M
authors.initials: KM
authors.lastname: Shen