论文标题
量子气中排斥的费米和玻色极性
Repulsive Fermi and Bose Polarons in Quantum Gases
论文作者
论文摘要
当移动杂质与许多粒子背景的基本激发耦合时,形成二极管准颗粒。在超低原子领域,对相关杂质问题的研究在过去15年中引起了人们的兴趣越来越大。极性的准粒子性能对于我们了解在超低原子气体和固态中实现的多种范式量子多体系统至关重要,从玻色纤维不平衡和费米 - 费米混合物到费米的哈伯德模型。在这篇局部综述中,我们专注于所谓的排斥极化子分支,在具有潜在有吸引力的相互作用(例如Ultracold Atomic混合物)的系统中,它是一种激动的多体状态,其特征是杂质与周围介质之间的有效排斥。我们简要说明了当前对排斥偏光元特性的理论和实验理解,即嵌入了费尔米金和玻色子媒体中的杂质,我们重点介绍了值得未来研究的开放问题。
Polaron quasiparticles are formed when a mobile impurity is coupled to the elementary excitations of a many-particle background. In the field of ultracold atoms, the study of the associated impurity problem has attracted a growing interest over the last fifteen years. Polaron quasiparticle properties are essential to our understanding of a variety of paradigmatic quantum many-body systems realized in ultracold atomic gases and in the solid state, from imbalanced Bose-Fermi and Fermi-Fermi mixtures to fermionic Hubbard models. In this topical review, we focus on the so-called repulsive polaron branch, which emerges as an excited many-body state in systems with underlying attractive interactions such as ultracold atomic mixtures, and is characterized by an effective repulsion between the impurity and the surrounding medium. We give a brief account of the current theoretical and experimental understanding of repulsive polaron properties, for impurities embedded in both fermionic and bosonic media, and we highlight open issues deserving future investigations.