Superconducting PdTe Thin Film Via Topotactic Transformation, Toward Topological Superconductors

Hee Taek Yi; Min Ge; Renjie Xie; Colby J. Stoddard; David H. Yi; Xiaoyu Yuan; Xiong Yao; Seongshik Oh

doi:10.1021/acsanm.6c00907

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arXiv · 2605.20437

Superconducting PdTe Thin Film Via Topotactic Transformation, Toward Topological Superconductors

Hee Taek Yi·Min Ge·Renjie Xie·Colby J. Stoddard·David H. Yi·Xiaoyu Yuan·Xiong Yao·Seongshik Oh

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Abstract

Topological superconductors (TSCs) hosting Majorana zero modes (MZMs) offer a pathway to fault-tolerant quantum computation. PdTe is a promising TSC candidate due to its topological surface states and a reasonable superconducting critical temperature of ~4.5 K. However, it has been challenging to grow PdTe thin films with bulk-like superconducting properties. Here, we show that high-quality, superconducting PdTe thin films can be grown using molecular beam epitaxy (MBE). The films exhibit a sharp superconducting transition (T_onset = 4.43 K with transition width of 0.06 K), comparable to that of bulk crystals. This was made possible via a topotactic transformation from a PdTe_2 buffer layer to a PdTe phase by growing Pd on top under Te-deficient conditions. Structural and transport analyses confirm the NiAs-type structure of PdTe, as well as its two-dimensional superconducting behavior and excellent air stability. These findings suggest that the MBE-grown PdTe films and their heterostructures are a promising platform for topological superconductivity and Majorana physics.

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Hee Taek Yi, Min Ge, Renjie Xie, Colby J. Stoddard, David H. Yi, Xiaoyu Yuan, Xiong Yao, Seongshik Oh. 2026-05-19. Superconducting PdTe Thin Film Via Topotactic Transformation, Toward Topological Superconductors. https://doi.org/10.1021/acsanm.6c00907

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