[论文解读] Reversible tuning of magnetic order and intrinsic superconductivity in strained FeTe thin films via stoichiometry control

Hao Xu, Jing Jiang+12 more|arXiv (Cornell University)|Feb 16, 2026

Iron-based superconductors research被引用 0

一句话总结

作者通过在在 SrTiO3 上生长的裸 FeTe 薄膜中对 Fe 的精确化学计量，能够抑制长程磁性并诱导可逆的本征超导性（约 10 K）。

ABSTRACT

FeTe is a prototypical parent compound of iron-based superconductors. While bulk FeTe is non-superconducting with a long-range bicollinear antiferromagnetic order, superconductivity has been achieved in thin films. However, the approaches usually involve complex oxygen incorporation or interfacial effects, the microscopic mechanisms of which remain elusive. Here, we prepare high-purity, bare FeTe thin films on SrTiO3 and investigate their magnetic and superconducting states combining both microscopic and macroscopic characterizations. By reducing the interstitial Fe impurities, we successfully suppress the long-range antiferromagnetic order, enhance the quasiparticle coherence and induce superconductivity at ~10 K. Moreover, this process is readily reversible by tuning the Fe concentration. Our findings reveal that precise stoichiometric control is sufficient to induce intrinsic superconductivity in strained FeTe thin films. This work provides insights into the competition between magnetism and superconductivity in iron chalcogenides, and supplies a robust pathway for developing stable, high-purity superconducting FeTe films.

研究动机与目标

• 了解化学计量如何控制应受应力的 FeTe 薄膜中的磁序和超导性。
• 证明减少间位 Fe 杂质可抑制反铁磁性并诱导超导性。
• 展示通过 Fe 浓度调控实现过程的可逆性。
• 提供铁族硫族化物中磁性与超导性竞争的见解。

提出的方法

• 在 SrTiO3 基板上制备高纯度、裸 FeTe 薄膜。
• 控制间位 Fe 杂质以调节磁性和电子态。
• 用显微和宏观探针表征磁序和超导性。
• 通过调节 Fe 浓度实现可逆性。
• 将超导出现与准粒子相干增强相关联。

实验结果

研究问题

• RQ1 在应力 FeTe 薄膜中，精确的 Fe 化学计量是否可以在不需要氧或界面工程的情况下实现本征超导性？
• RQ2 减少间位 Fe 是否会抑制长程双直线反铁磁序并增强准粒子相干性？
• RQ3 通过调节 Fe 浓度，磁性到超导性的调控是否可逆？
• RQ4 Fe 含量、磁性序列与 FeTe 薄膜的超导转变温度之间的关系是什么？

主要发现

• 减少间位 Fe 杂质抑制 FeTe 薄膜的长程反铁磁序。
• 在受应力、高纯薄膜中约在 10 K 出现超导性。
• 通过调节 Fe 浓度，磁性到超导性的调控是可逆的。
• 精确的化学计量控制足以在受应力 FeTe 中诱导本征超导性。
• 结果揭示铁 硒族化合物中磁性与超导性之间的竞争。