2 research outputs found
Intrinsic and extrinsic conduction contributions at nominally neutral domain walls in hexagonal manganites
Conductive and electrostatic atomic force microscopy (cAFM and EFM) are used
to investigate the electric conduction at nominally neutral domain walls in
hexagonal manganites. The EFM measurements reveal a propensity of mobile charge
carriers to accumulate at the nominally neutral domain walls in ErMnO3, which
is corroborated by cAFM scans showing locally enhanced d.c. conductance. Our
findings are explained based on established segregation enthalpy profiles for
oxygen vacancies and interstitials, providing a microscopic model for previous,
seemingly disconnected observations ranging from insulating to conducting
domain wall behavior. In addition, we observe variations in conductance between
different nominally neutral walls that we attribute to deviations from the
ideal charge-neutral structure within the bulk, leading to a superposition of
extrinsic and intrinsic contributions. Our study clarifies the complex
transport properties at nominally neutral domain walls in hexagonal manganites
and establishes new possibilities for tuning their electronic response based on
oxidation conditions, opening the door for domain-wall based sensor technology.Comment: 5 pages, 3 figure