2017年2月

# Bose-Einstein-condensate polaron in harmonic trap potentials in the weak-coupling regime: Lee-Low-Pines-type approach

PHYSICAL REVIEW A
• Eiji Nakano
• ,
• Hiroyuki Yabu
• ,
• Kei Iida

95
2

DOI
10.1103/PhysRevA.95.023626

AMER PHYSICAL SOC

We have calculated the zero-temperature binding energy of a single impurity atom immersed in a Bose-Einstein condensate (BEC) of ultracold atoms. The impurity and the condensed atoms are trapped in the respective axially symmetric harmonic potentials, where the impurity interacts with bosonic atoms in the condensate via low-energy s-wave scattering. In this case, bosons are excited around the impurity to form a quasiparticle, namely, a BEC polaron. We have developed a variational method, a la Lee-Low-Pines (LLP), for description of the polaron that has a conserved angular momentum around the symmetric axis. We find from numerical results that the binding between the impurity and the excited bosons breaks the degeneracy of the impurity energy with respect to the total angular momentum of the polaron. The angular momentum is partially shared by the excited bosons in a manner that is similar to the drag effect on the polaron momentum by a phonon cloud in the LLP theory for the electron-phonon system.

Web of Science ® 被引用回数 : 8

リンク情報
DOI
https://doi.org/10.1103/PhysRevA.95.023626
Web of Science