Properties of La${}_{0.7}$Ca${}_{0.3}$MnO${}_3$ Under Extreme Tensile Strain

Abstract

The complex phase diagram of manganites with simultaneously active spin, charge, orbital, and lattice degrees of freedom continues providing surprises. In a recent groundbreaking experiment, membranes of the perovskite manganite La${}_{0.7}$Ca${}_{0.3}$MnO${}_3$ (LCMO) deposited on a flexible polymer layer were strained up to 8\% [S.~S. Hong {\it et al.}, Science {\bf 368}, 71 (2020)], much more than achieved by regular strain induced by a rigid substrate. By increasing this strain a metal-insulator transition was reported. Here we reproduce the results of the experiments using Monte Carlo simulations of the two-orbital double-exchange model including Jahn-Teller distortions, at hole density $x=1/3$. The full phase diagram with varying temperature and Jahn-Teller coupling $\lambda$ is presented. When the bandwidth $W$ of mobile electrons is reduced, thus when the effective Jahn-Teller coupling $\lambda /W$ is increased, a metal-insulator transition is found in our simulations, between a ferromagnetic metallic state with uniform charge distribution and an insulator with diagonal charge stripes that retains its ferromagnetic character. In between the hole-rich diagonals, staggered orbital order occurs. We also report resistivity and magnetization measurements alongside with spin correlations and charge structure factors. Our overall conclusions are in agreement with the recent experimental and density functional theory results by Hong {\it et al.}, and we confirm much earlier ground state predictions of striped ferromagnetic order using energy optimization techniques by T. Hotta {\it et al.}, Phys. Rev. Lett. {\bf 86}, 4922 (2001). The experimental observation of one of the states predicted by theory suggests that diagonal stripes could be achieved at other hole densities as well, such as $x=1/4$, if LCMO membranes with that hole doping were subject to similar strains.

9 pages, 6 figures

References in corpus (7)

• Competing Ferromagnetic and Charge-Ordered States in Models for Manganites: the Origin of the CMR Effect
• Insulator to Metal Transition Induced by Disorder in a Model for Manganites
• Unveiling First Order CMR Transitions in the Two-Orbital Model for Manganites
• Striped Multiferroic Phase in Double-Exchange Model for Quarter-Doped Manganites
• Competition between covalent bonding and charge transfer at complex-oxide interfaces
• Emergent dimensional reduction of the spin sector in a model for narrow-band manganites
• Electronic self-organization in the single-layer manganite $\mathrm{P}{\mathrm{r}}_{1-x}\mathrm{C}{\mathrm{a}}_{1+x}\mathrm{Mn}{\mathrm{O}}_4$

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