  The highly anisotropic resistivities in strained manganites are theoretically
studied using the two-orbital double-exchange model. At the nanoscale, the
anisotropic double-exchange and Jahn-Teller distortions are found to be
responsible for the robust anisotropic resistivities observed here via Monte
Carlo simulations. An unbalanced in the population of orbitals caused by strain
is responsible for these effects. In contrast, the anisotropic superexchange is
found to be irrelevant to explain our results. Our model study suggests that
highly anisotropic resistivities could be present in a wide range of strained
manganites, even without (sub)micrometer-scale phase separation. In addition,
our calculations also confirm the formation of anisotropic clusters in
phase-separated manganites, which magnifies the anisotropic resistivities.
