准粒子的快速冷却玻色-爱因斯坦凝聚
介观与纳米尺度物理
2020-07-02 v3 其他凝聚态物理
摘要
玻色-爱因斯坦凝聚（BEC）这一基本现象已在真实粒子和准粒子的不同系统中被观测到。真实粒子的凝聚通过大幅降温实现，而准粒子则需要借助辐照外部注入玻色子的机制。本文提出一种新颖且普适的方法来实现准粒子的BEC，并以磁子作为玻色粒子模型系统进行了实验验证。该方法的关键在于引入磁子与声子浴之间的非平衡态。在加热至高温后，声子温度突降（在磁子系统的时间尺度上近似瞬时），导致大量非相干磁子过剩。这些磁子的后续谱重分布触发了玻色-爱因斯坦凝聚。
引用
@article{arxiv.1612.07305,
title = {Bose-Einstein Condensation of Quasi-Particles by Rapid Cooling},
author = {M. Schneider and T. Brächer and D. Breitbach and V. Lauer and P. Pirro and D. A. Bozhko and A. A. Serga and H. Yu. Musiienko-Shmarova and B. Heinz and Q. Wang and T. Meyer and F. Heussner and S. Keller and E. Th. Papaioannou and B. Lägel and T. Löber and V. S. Tiberkevich and A. N. Slavin and C. Dubs and B. Hillebrands and A. V. Chumak},
journal= {arXiv preprint arXiv:1612.07305},
year = {2020}
}
备注
In contrast to the previous version additional information has been added. The chemical potential was derived from BLS measurements, the influence of the spin Seebeck effect is discussed more extensively in the Supplement with respect to the theoretical model and the rapid cooling has been realized in Au/Al/YIG structures where no substantial contribution of the spin Seebeck effect is expected