标题： 从头算研究晶格上的中子和费米极化子 显示英文标题

标题： Ab initio study of the neutron and Fermi polarons on the lattice

摘要： 我们使用了格点上的辅助场量子蒙特卡罗（AFQMC）多体方法来研究费米杂质与自旋极化费米子背景海相互作用的状态方程。 杂质，或极化子，在冷原子和核物理中都是一个有趣的系统。 我们的方法是通用的，我们能够直接研究这些不同范围内的极化子。 我们首先研究了单位制下的费米极化子以及广泛范围的散射长度，并与之前理论和实验研究进行比较。 然后我们探索了中子极化子，这已被证明对核物理是一个重要的约束。 我们还采用了最近开发的参数矩阵模型，以模拟格点上的AFQMC对两体问题的解，从而根据Lüscher公式直接将格点哈密顿量参数调整到周期性盒子中的两体能量，以加速调优过程。 我们在冷原子和核物理背景下对极化子的格点量子蒙特卡罗结果可以作为未来理论和实验研究的严格基准。 显示英文摘要

摘要： We have used the auxiliary-field Quantum Monte Carlo (AFQMC) many-body approach on the lattice to study the equation of state for a fermionic impurity interacting with a background sea of spin-polarized fermions. The impurity, or polaron, is an interesting system in both cold atomic and nuclear physics. Our approach is general, and we are able to straightforwardly study the polaron across these regimes. We first study the Fermi polaron at unitarity and for a wide range of scattering lengths, comparing against previous theoretical and experimental studies. We then explore the neutron polaron which has been shown to be an important constraint for nuclear physics. We have also employed the recently developed parametric matrix model to emulate AFQMC solutions to the two-body problem on the lattice, to accelerate the tuning of our lattice Hamiltonian parameters directly to two-body energies in a periodic box, following Lscher's formula. Our lattice Quantum Monte Carlo results for the polaron in both a cold atomic and nuclear physics context can serve as stringent benchmarks for future theoretical and experimental research.