论文标题
一维偶极胶气中基本激发的阻尼
Damping of elementary excitations in one-dimensional dipolar Bose gases
论文作者
论文摘要
在存在偶极相互作用的情况下，玻色气体的激发光谱可以获取局部最小值。相应的准颗粒称为旋转。它们被凝并且不会在零温度下衰减。在这里，我们研究了低温下一维bose气体中旋转的腐烂。这主要是由于旋转子上热声子的反向散射。最终的速率尺度具有第三个温度的功率，并且与固化相跃迁附近的Roton Gap的第六功率成反比。此处使用的流体动力学方法使我们能够在几乎任何动力上找到准粒子的衰减速率，对颗粒间相互作用的确切形式的假设最少。我们的结果是描述偶极气体中所有耗散现象的必要先决条件，并且具有直接的实验相关性。
In the presence of dipolar interactions the excitation spectrum of a Bose gas can acquire a local minimum. The corresponding quasiparticles are known as rotons. They are gaped and do not decay at zero temperature. Here we study the decay of rotons in one-dimensional Bose gases at low temperatures. It predominantly occurs due to the backscattering of thermal phonons on rotons. The resulting rate scales with the third power of temperature and is inversely proportional to the sixth power of the roton gap near the solidification phase transition. The hydrodynamic approach used here enables us to find the decay rate for quasiparticles at practically any momenta, with minimal assumptions on the exact form of the interparticle interactions. Our results are an essential prerequisite for the description of all the dissipative phenomena in dipolar gases and have direct experimental relevance.
