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Weak charge-lattice coupling requires reinterpretation of stripes of charge order in La1-xCaxMnO3

J. C. Loudon·S. Cox·A. J. Williams·J. P. Attfield·P. B. Littlewood·P. A. Midgley·N. D. Mathur
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Abstract

Modulations in manganites attributed to stripes of charge/orbital/spin order are thought to result from strong electron-lattice interactions that lock the superlattice and parent lattice periodicities. Surprisingly in La1-xCaxMnO3(x>0.5, 90 K), convergent beam (3.6 nm spot) electron diffraction patterns rule out charge stacking faults and indicate a superlattice with uniform periodicity. Moreover, large area electron diffraction peaks are sharper than simulations with stacking faults. Since the electron-lattice coupling does not lock the two periodicities (to yield stripes) it may be too weak to strongly localise charge.

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J. C. Loudon, S. Cox, A. J. Williams, J. P. Attfield, P. B. Littlewood, P. A. Midgley, N. D. Mathur. 2005-01-26. Weak charge-lattice coupling requires reinterpretation of stripes of charge order in La1-xCaxMnO3. https://doi.org/10.1103/physrevlett.94.097202

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