论文标题
掺杂的自旋液体候选者中的超流体密度降低
Reduced superfluid density in a doped spin liquid candidate
论文作者
论文摘要
量子自旋液体（QSL）将是超导性的外来阶段。掺杂QSL的有前途的候选者是有机三角晶格系统Kappa-（Bedt-TTF）4HG2：89BR8，它具有QSL性质的非Fermi液体和磁性，并在冷却时显示出超导性。在这里，我们报告说其超流体密度异常降低，表明存在实质性不一致的光谱重量和弱超导相位刚度。此外，超导过渡温度与名义费米温度的比率高达0.1，超出了典型BCS值的数量级。这些观察到没有竞争订单的系统中的这些观察结果，这些订单使不足的酸奶病中的类似问题复杂化，这使掺杂的莫特绝缘子中神秘的缺失的超流体密度有线索。
A quantum spin liquid (QSL) would be an exotic stage for superconductivity. A promising candidate for a doped QSL is the organic triangular-lattice system, kappa-(BEDT-TTF)4Hg2:89Br8, which hosts a non-Fermi liquid and magnetism of a QSL nature and shows superconductivity upon cooling. Here, we report that its superfluid density is anomalously reduced, indicating the existence of substantial incoherent spectral weight and weak superconducting phase stiffness. Moreover, the ratio of the superconducting transition temperature to the nominal Fermi temperature is as large as 0.1, orders of magnitude beyond typical BCS values. These observations in a system free from competing orders that complicate the similar issue in underdoped cuprates give a clue to the enigmatic missing superfluid density in doped Mott insulators.
