Weak charge-lattice coupling requires reinterpretation of stripes of charge order in La1-xCaxMnO3 -: art. no. 097202
Weak charge-lattice coupling requires reinterpretation of stripes of charge order in La1-xCaxMnO3 -: art. no. 097202
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DOI：
10.1103/physrevlett.94.097202
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发表时间：
2005-03-11
影响因子：
8.6
通讯作者：
Mathur, ND
中科院分区：
文献类型：
--
作者：
Loudon, JC;Cox, S;Mathur, ND
锰氧化物中归因于电荷/轨道/自旋顺序条纹的调制被认为是由锁定超晶格和母晶格周期性的强电子-晶格相互作用引起的。令人惊讶的是，在La 1-xCaxMnO 3（x > 0：5; 90 K），会聚束（3.6 nm斑点）电子衍射图案排除了电荷堆垛层错，并表明具有均匀的周期性的超晶格。此外，大面积电子衍射峰比具有堆垛层错的模拟更尖锐。由于电子-晶格耦合没有锁定两个周期（产生条纹），它可能太弱而不能强烈地局部化电荷。
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 localize charge.