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Chain-oxygen ordering in twin-free YBa2Cu3O6+x single crystals driven by 20 keV electron irradiation

H. W. Seo·Q. Y. Chen·M. N. Iliev·N. Kolev·U. Welp·C. Wang·Tom H. Johansen·Wei-Kan Chu
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Abstract

We have examined the effects of 20 keV electron irradiation on [-Cu(1)-O(1)-]n chain oxygen arrangements in oxygen deficient but otherwise twin-free YBa2Cu3O6+x single crystals. Comparison of polarized Raman spectra of non-irradiated and irradiated areas provides evidence that electron bombardments instigate the collective hopping of oxygen atoms either from an interstitial at O(5) site to a vacant O(1) chain site or by reshuffling the chain segments to extend the average length of chains without changing the overall oxygen content. This oxygen ordering effect, while counter-intuitive, is analogous to that found in the photoexcitation induced ordering in which temporal charge imbalance from electron-hole pair creation by inelastic scattering of incident electrons causes a local lattice distortion which brings on the atomic rearrangements.

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H. W. Seo, Q. Y. Chen, M. N. Iliev, N. Kolev, U. Welp, C. Wang, Tom H. Johansen, Wei-Kan Chu. 2005-03-09. Chain-oxygen ordering in twin-free YBa2Cu3O6+x single crystals driven by 20 keV electron irradiation. https://doi.org/10.1103/physrevb.72.052501

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