论文标题
纯列量子临界点伴随着超导圆顶
Pure nematic quantum critical point accompanied by a superconducting dome
论文作者
论文摘要
当物质的破坏阶段被抑制至绝对零的量子临界点（QCP）时，量子力学波动增殖。这种波动会导致非常规的超导性，这是通过相关材料中经常发现的磁性QCP附近发现的超导圆顶所证明的。但是，尚不清楚这种超导性机制是否适用于电子列相的QCP，其特征是旋转对称性破裂。在这里，我们从系统的弹性测量测量中证明了非磁性FESE $ _ {1-x} $ te $ _ {x} $表现出电子nematic QCP，显示出不同的nematic敏感性。这一发现在基于FESE的超导体中建立了两个nematic QCP，并具有对比伴随的相图。在fese $ _ {1-x} $ te $ _ {x} $中，超导圆顶以QCP为中心，而FESE $ _ {1-x} $ s $ _ {x} $ show no qcp-qcp cp cp cy of qcp-speciped-not qcp cypiped-tociped comped-tociped of qcp oversiped of qcp oversiped of qcp camp overciped of Supercondoctivation的增强。我们发现这种差异与列和自旋波动的相对强度有关。我们在FESE $ _ {1-x} $ te $ _ {x} $中的结果提出了第一种情况，以支持与纯列QCP相关的超导圆顶。
When a symmetry-breaking phase of matter is suppressed to a quantum critical point (QCP) at absolute zero, quantum-mechanical fluctuations proliferate. Such fluctuations can lead to unconventional superconductivity, as evidenced by the superconducting domes often found near magnetic QCPs in correlated materials. However, it remains unclear whether this superconductivity mechanism holds for QCPs of the electronic nematic phase, characterized by rotational symmetry breaking. Here, we demonstrate from systematic elastoresistivity measurements that nonmagnetic FeSe$_{1-x}$Te$_{x}$ exhibits an electronic nematic QCP showing diverging nematic susceptibility. This finding establishes two nematic QCPs in FeSe-based superconductors with contrasting accompanying phase diagrams. In FeSe$_{1-x}$Te$_{x}$, a superconducting dome is centered at the QCP, whereas FeSe$_{1-x}$S$_{x}$ shows no QCP-associated enhancement of superconductivity. We find that this difference is related to the relative strength of nematic and spin fluctuations. Our results in FeSe$_{1-x}$Te$_{x}$ present the first case in support of the superconducting dome being associated with the pure nematic QCP.
