论文标题
一维少量特里米昂系统中的磁杂质
Magnetic impurity in a one-dimensional few-fermion system
论文作者
论文摘要
我们在陷阱中心存在类似磁点的杂质的情况下，在一维谐波电位中介绍了自旋 - $ \ frac {1} {2} $ fermions。该模型代表了$ s $波超导体附近的磁杂质的几个体型类似物。对于几个颗粒，我们已经找到了具有不同费米昂奇偶群的扇区之间的地面水平交叉。我们将这种交叉解释为量子相变的几个体体前体，当杂质“破裂”库珀对时发生。通过分析动量空间中的密度密度相关性，进一步证实了这一图像。最后，我们讨论如何使用现有的冷原子平台实现系统。
We present a numerical analysis of spin-$\frac{1}{2}$ fermions in a one-dimensional harmonic potential in the presence of a magnetic point-like impurity at the center of the trap. The model represents a few-body analogue of a magnetic impurity in the vicinity of an $s$-wave superconductor. Already for a few particles we find a ground-state level crossing between sectors with different fermion parities. We interpret this crossing as a few-body precursor of a quantum phase transition, which occurs when the impurity `breaks' a Cooper pair. This picture is further corroborated by analyzing density-density correlations in momentum space. Finally, we discuss how the system may be realized with existing cold-atoms platforms.
