Quantum Phase Transition of Correlated Iron-Based Superconductivity in LiFe1-xCoxAs
Quantum Phase Transition of Correlated Iron-Based Superconductivity in LiFe1-xCoxAs
复制标题
LiFe1-xCoxAs 中相关铁基超导性的量子相变
DOI：
10.1103/physrevlett.123.217004
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发表时间：
2019
影响因子：
8.6
通讯作者：
Chang
中科院分区：
文献类型：
--
作者：
Yin Jia-Xin;Zhang Songtian S.;Dai Guangyang;Zhao Yuanyuan;Kreisel Andreas;Macam Gennevieve;Wu Xianxin;Miao Hu;Huang Zhi-Quan;Martiny Johannes H. J.;Andersen Brian M.;Shumiya Nana;Multer Daniel;Litskevich Maksim;Cheng Zijia;Yang Xian;Cochran Tyler A.;Chang
非传统的库珀配对和与原子尺度缺陷相关的量子态之间的相互作用是研究的前沿，有许多悬而未决的问题。到目前为止，只有少数高温超导体允许以广泛可调的方式研究这种复杂的物理学。我们使用扫描隧道显微镜来成像Co原子对基态的电子碰撞。我们观察到，杂质逐步抑制全球超导间隙，并在差距边缘附近引入低能态，超导性保持在强耦合极限。出乎意料的是，在库珀对相干性被完全破坏之前，完全打开的能隙演变成节点状态。我们的系统理论分析表明，这些新的观测结果可以用安波超导体中的玻恩极限散射效应来定量解释，揭示了超导体到金属量子相变的驱动力。
The interplay between unconventional Cooper pairing and quantum states associated with atomic scale defects is a frontier of research with many open questions. So far, only a few of the high-temperature superconductors allow this intricate physics to be studied in a widely tunable way. We use scanning tunneling microscopy to image the electronic impact of Co atoms on the ground state of thesystem. We observe that impurities progressively suppress the global superconducting gap and introduce low energy states near the gap edge, with the superconductivity remaining in the strong-coupling limit. Unexpectedly, the fully opened gap evolves into a nodal state before the Cooper pair coherence is fully destroyed. Our systematic theoretical analysis shows that these new observations can be quantitatively understood by the nonmagnetic Born-limit scattering effect in an-wave superconductor, unveiling the driving force of the superconductor to metal quantum phase transition.