论文标题
深度退化SU（$ n $）的热力学 - 对称费米气体
Thermodynamics of a deeply degenerate SU($N$)-symmetric Fermi gas
论文作者
论文摘要
多体量子系统可以表现出与其经典同行无与伦比的惊人对称程度。在实际材料中，SU（$ n $）对称性是一种理想化，但这种对称性在完全可控制的超低碱 - 地球原子气体中被原始实现。在这里，我们研究了$^{87} $ sr原子的SU（$ n $） - 对称的费米液体，可以将$ n $调用至10。在深度退化的状态中，我们通过精确测量密度波动和扩展动力学的精确测量，这些动力与SU下的SU $ N $ sy（$ n $ n $ n $ n $ n $ n $ n $ n）相对的影响（$ n可忽略的交互参数。考虑到这些效果，我们证明了对费米能量的一百分之一的温度法。我们还展示了准备退化费米海的创纪录速度，在3秒钟内达到$ t/t_f = 0.12 $，由su（$ n $）对称互动启用。加上这是一种新的自旋偏振方法，可以在频段绝缘仪上操作3D光学晶格时钟。
Many-body quantum systems can exhibit a striking degree of symmetry unparalleled by their classical counterparts. While in real materials SU($N$) symmetry is an idealization, this symmetry is pristinely realized in fully controllable ultracold alkaline-earth atomic gases. Here, we study an SU($N$)-symmetric Fermi liquid of $^{87}$Sr atoms, where $N$ can be tuned to be as large as 10. In the deeply degenerate regime, we show through precise measurements of density fluctuations and expansion dynamics that the large $N$ of spin states under SU($N$) symmetry leads to pronounced interaction effects in a system with a nominally negligible interaction parameter. Accounting for these effects we demonstrate thermometry accurate to one-hundredth of the Fermi energy. We also demonstrate record speed for preparing degenerate Fermi seas, reaching $T/T_F = 0.12$ in under 3 s, enabled by the SU($N$) symmetric interactions. This, along with the introduction of a new spin polarizing method, enables operation of a 3D optical lattice clock in the band insulating-regime.
