Tackling Fermi polaron problem with a new variational approach
演讲者
石悦然
时间
2025年08月06日 10:00 至 12:00
地点
Shuangqing-B627
线上
Zoom 230 432 7880
(BIMSA)
摘要
The polaron problem describes an impurity interacting with a background medium, representing the highly imbalanced limit of a two-component system. Polarons are classified as Bose or Fermi by the majority statistics, with the Fermi case allowing impurity-fermion binding and interaction-driven transitions. Ultracold atomic gases provide an ideal platform, and various theoretical approaches have been developed to explore their properties.
We study low-dimensional Fermi polarons using a non-Gaussian variational approach. By employing the Lee-Low-Pines transformation, we decouple the impurity and then determine the ground state at fixed momentum via imaginary-time evolution. For conventional Fermi polarons, our results agree with previous studies and reveal a smooth crossover from polaron to molecular states. Extending to interacting backgrounds, we find that stronger interactions drive a continuous evolution from Fermi to Bose polarons.
We study low-dimensional Fermi polarons using a non-Gaussian variational approach. By employing the Lee-Low-Pines transformation, we decouple the impurity and then determine the ground state at fixed momentum via imaginary-time evolution. For conventional Fermi polarons, our results agree with previous studies and reveal a smooth crossover from polaron to molecular states. Extending to interacting backgrounds, we find that stronger interactions drive a continuous evolution from Fermi to Bose polarons.