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arXiv · 1908.11128

Evidence for weak antilocalization-weak localization crossover and metal-insulator transition in CaCu$_{3}$Ru$_{4}$O$_{12}$ thin films

Subhadip Jana·Shwetha G. Bhat·B. C. Behera·L. Patra·P. S. Anil Kumar·B. R. K. Nanda·D. Samal
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Abstract

Artificial confinement of electrons by tailoring the layer thickness has turned out to be a powerful tool to harness control over competing phases in nano-layers of complex oxides. We investigate the effect of dimensionality on transport properties of $d$-electron based heavy-fermion metal CaCu$_{3}$Ru$_{4}$O$_{12}$. Transport behavior evolves from metallic to localized regime upon reducing thickness and a metal insulator transition is observed below 3 nm film thickness for which sheet resistance crosses $h/e^{2} \sim 25~$k$\Omega$, the quantum resistance in 2D. Magnetotransport study reveals a strong interplay between inelastic and spin-orbit scattering lengths upon reducing thickness, which results in weak antilocalization (WAL) to weak localization (WL) crossover in magnetoconductance.

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Subhadip Jana, Shwetha G. Bhat, B. C. Behera, L. Patra, P. S. Anil Kumar, B. R. K. Nanda, D. Samal. 2019-08-29. Evidence for weak antilocalization-weak localization crossover and metal-insulator transition in CaCu$_{3}$Ru$_{4}$O$_{12}$ thin films. https://doi.org/10.1209/0295-5075/133/17005

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