俄罗斯国家研究高等经济大学的Azat F. Aminov与俄罗斯科学院微电子技术与高纯材料研究所的Alexey A. Sokolik等人合作并取得一项新进展。经过不懈努力，他们揭示双组分原子玻色-爱因斯坦凝聚体中的有限频率法向和超流体曳引效应。相关研究成果已于2024年7月18日在国际知名学术期刊《物理评论A》上发表。

据悉，由相互作用的粒子组成的双组分系统可以显示组分内输运效应和组分间夹带(或曳引)效应。超流体存在时，在双流体模型框架下，组分内输运以耗散电导率和超流体重量为特征，组分间夹带产生法向和非耗散曳引效应。

本文基于博戈留波夫理论，对空间均匀双组分原子玻色-爱因斯坦凝聚态的所有这些效应进行了统一处理，特别关注了曳引效应。研究人员在考虑准粒子阻尼的情况下，计算有限频率的组分内和组分间电导率，研究人员推导出适用于低频的类德鲁德近似和适用于高频的类洛伦兹近似，并在数值上验证了自旋到密度博戈留波夫准粒子转换共振能量附近的类德鲁德近似。作为双组分原子系统可能的物理实现，研究人员考虑了三维玻色-玻色混合物和紧密间隔的磁偶极原子双层系统。

附：英文原文

Title: Finite-frequency normal and superfluid drag effects in two-component atomic Bose-Einstein condensates

Author: Azat F. Aminov, Alexey A. Sokolik, Yurii E. Lozovik

Issue&Volume: 2024/07/18

Abstract: Two-component systems consisting of mutually interacting particles can demonstrate both intracomponent transport effects and intercomponent entrainment (or drag) effects. In the presence of superfluidity, the intracomponent transport is characterized by dissipative conductivity and superfluid weight in the framework of two-fluid model, and intercomponent entrainment gives rise to normal and nondissipative drag effects. We present unified treatment of all these effects for spatially homogeneous two-component atomic Bose-Einstein condensates based on the Bogoliubov theory, focusing specifically on the drag effects. Calculating finite-frequency intra- and intercomponent conductivities with taking into account quasiparticle damping, we derive and numerically check analytical Drude-like approximations applicable at low frequencies and Lorentz-like approximations applicable at higher frequencies in the vicinity of the resonant energy of spin-to-density Bogoliubov quasiparticle conversion. As possible physical realizations of two-component atomic systems, we consider three-dimensional Bose-Bose mixtures and closely spaced two-layered systems of magnetic dipolar atoms.

DOI: 10.1103/PhysRevA.110.013318

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.013318