论文标题
量子临界金属的比热
Specific Heat of a Quantum Critical Metal
论文作者
论文摘要
我们使用无标志的量子蒙特卡洛模拟研究了伊辛列量量临界点（QCP）附近的特定热量$ c $。向QCP冷却，我们发现了一个广泛的温度，即使$ c/t $接近非相互作用带结构预期的价值，即使对于中等大的耦合强度也是如此。在较低的温度下，我们观察到$ c/t $的迅速上升，然后随着系统的超导而下降至零。旋转易感性开始在增强$ c/t $ onsets的温度下下降，这很可能是由于与超导波动相关的差距的打开。这些发现表明，在可比的能量尺度上，超导性和非Fermi液体行为（体现在有效质量的增强中）。我们通过分析扰动计算支持这些结论。
We investigate the specific heat, $c$, near an Ising nematic quantum critical point (QCP), using sign problem-free quantum Monte Carlo simulations. Cooling towards the QCP, we find a broad regime of temperature where $c/T$ is close to the value expected from the non-interacting band structure, even for a moderately large coupling strength. At lower temperature, we observe a rapid rise of $c/T$, followed by a drop to zero as the system becomes superconducting. The spin susceptibility begins to drop at roughly the same temperature where the enhancement of $c/T$ onsets, most likely due to the opening of a gap associated with superconducting fluctuations. These findings suggest that superconductivity and non-Fermi liquid behavior (manifested in an enhancement of the effective mass) onset at comparable energy scales. We support these conclusions with an analytical perturbative calculation.
