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arXiv · 2010.16379

Epitaxial stabilization of (111)-oriented frustrated quantum pyrochlore thin films

Fangdi Wen·Tsung-Chi Wu·Xiaoran Liu·Michael Terilli·Mikhail Kareev·Jak Chakhalian
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Abstract

Frustrated rare-earth pyrochlore titanates, Yb$_2$Ti$_2$O$_7$, and Tb$_2$Ti$_2$O$_7$ have been proposed as promising candidates to realize quantum spin ice (QSI). Multiple exotic quantum phases, including Coulombic ferromagnet, quantum valence-bond solid, and quadrupolar ordering, have been predicted to emerge in the QSI state upon application of a (111)-oriented external magnetic field. Here, we report on the primal successful layer-by-layer growth of ultra-thin films of frustrated quantum pyrochlores, R$_2$Ti$_2$O$_7$ (R = Er, Yb, and Tb), along the (111) direction. We confirm their high crystallinity and proper chemical composition by a combination of methods, including in-situ RHEED, x-ray diffraction, reciprocal space mapping, and x-ray photoelectron spectroscopy. The availability of large area (111)-oriented QSI structures with planar geometry offers a new complementary to the bulk platform to explore strain and magnetic field dependent properties in the quasi-2D limit.

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Fangdi Wen, Tsung-Chi Wu, Xiaoran Liu, Michael Terilli, Mikhail Kareev, Jak Chakhalian. 2020-10-30. Epitaxial stabilization of (111)-oriented frustrated quantum pyrochlore thin films. https://doi.org/10.1063/5.0035702

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