论文标题
量子关键超导体的异常热力学特性
Anomalous thermodynamic properties of quantum critical superconductors
论文作者
论文摘要
采用不同实验技术的最新高精度测量结果在伦敦穿透深度的掺杂依赖性中揭示了异常的峰值，该峰值伴随着与隐藏的抗fiferromagnetic量子关键点有关的最佳组成，伴随着铁 - 斑点超导的热容量的异常。我们认为有限温度效应可能是观察到的特征的原因。具体而言，我们表明，在超导圆顶下的量子临界磁波动会导致完全间隙超导体中特定的热和磁穿透深度的节点样温度依赖性。在超导间隙波动中存在线节点的情况下，可能会导致$ t $ - 线性穿透深度的相对斜率显着重新归一化，这在量子关键点最陡。我们获得的结果是一般的，可以超出我们使用的模型。
Recent high-precision measurements employing different experimental techniques have unveiled an anomalous peak in the doping dependence of the London penetration depth which is accompanied by anomalies in the heat capacity in iron-pnictide superconductors at the optimal composition associated with the hidden antiferromagnetic quantum critical point. We argue that finite temperature effects can be a cause of observed features. Specifically we show that quantum critical magnetic fluctuations under superconducting dome can give rise to a nodal-like temperature dependence of both specific heat and magnetic penetration depth in a fully gapped superconductor. In the presence of line nodes in the superconducting gap fluctuations can lead to the significant renormalization of the relative slope of $T$-linear penetration depth which is steepest at the quantum critical point. The results we obtain are general and can be applied beyond the model we use.
