AI 中文总结
本研究探究了浸没在有限弱相互作用二维玻色气体中的单个吸引型杂质，结合有限温度多体散射理论与路径积分蒙特卡罗方法分析其准粒子能量，发现吸引型玻色极化子可作为低维玻色气体相关物理的灵敏探针。
AI 中文摘要
二维量子气体提供了一个独特的研究场景，其中增强的热涨落、有限尺寸效应以及两体束缚态形成是内在交织在一起的。在本研究中，我们探究了浸没在有限、弱相互作用二维玻色气体中的单个吸引型杂质，有限尺寸通过引入红外动量尺度稳定了非零的凝聚分数，从而使得对该环境的Bogoliubov描述成为可能。我们采用一种混合方法，将有限温度多体散射理论与路径积分蒙特卡罗的输入相结合，分析了杂质准粒子在凝聚态和正常态下的能量。该红外尺度产生了一个声子激活温度，低于该温度时杂质能量几乎与温度无关。一旦可分辨的声子模式被热占据，它们的贡献就会与凝聚态耗竭产生竞争，从而形成极化子能量的非单调温度依赖关系。这些结果表明，吸引型玻色极化子可作为低维玻色气体中有限尺寸热涨落、声子修饰以及束缚态物理的灵敏探针。
英文摘要
Two-dimensional quantum gases provide a distinctive setting in which enhanced thermal fluctuations, finite-size effects, and two-body bound-state formation are intrinsically intertwined. In this work, we study a single attractive impurity immersed in a finite, weakly interacting two-dimensional Bose gas, where finite size stabilizes a nonzero condensate fraction by introducing an infrared momentum scale, thereby enabling a Bogoliubov description of the bath. Using a hybrid approach that combines finite-temperature many-body scattering theory with input from path-integral Monte Carlo, we analyze the impurity quasiparticle energy across the condensate and normal regimes. The infrared scale generates a phonon-activation temperature below which the impurity energy remains nearly temperature independent. Once the resolved phonon modes become thermally populated, their contribution competes with condensate depletion, producing a nonmonotonic temperature dependence of the polaron energy. These results suggest that attractive Bose polarons may serve as sensitive probes of finite-size thermal fluctuations, phonon dressing, and bound-state physics in low-dimensional Bose gases.
Comments14 pages, 7 figures
