论文标题
巨型Grüneisen参数在应变的超导量子旁道中：消失的铁电声子能量的结果
Giant Grüneisen parameter in a strain-tuned superconducting quantum paraelectric: A consequence of the vanishing ferroelectric phonon energy
论文作者
论文摘要
超导性和铁电性通常是不兼容的，因为前者需要自由载体，但是除非其浓度较低，否则后者通常会被自由载体抑制。在低载体浓度较低的钛酸盐的情况下，非常规超导性和铁电性相关。在这里，我们报告了理论和实验评估的Grüneisen参数，其拉伸应力下的差异表明增强超导顺序的主要声子模式是铁电横向软模式。这一发现排除了所有其他声子模式，这是导致钛酸斜纹斜纹斜纹肌层超导性增强的主要贡献者。此处显示的方法可以应用于许多其他量子材料。
Superconductivity and ferroelectricity are typically incompatible because the former needs free carriers, but the latter is usually suppressed by free carriers, unless their concentration is low. In the case of strontium titanate with low carrier concentration, unconventional superconductivity and ferroelectricity were shown to be correlated. Here, we report theoretically and experimentally evaluated Grüneisen parameters whose divergence under tensile stress indicates that the dominant phonon mode that enhances the superconducting order is the ferroelectric transverse soft-mode. This finding rules out all other phonon modes as the main contributors to the enhanced superconductivity in strained strontium titanate. This methodology shown here can be applied to many other quantum materials.
