论文标题
berezinskii-kosterlitz-通过消散的quasisolitons引起的无尽阶段
Berezinskii-Kosterlitz-Thouless phase induced by dissipating quasisolitons
论文作者
论文摘要
从理论上讲，我们研究了二维弱相互作用均匀bose气体中的声音传播。使用经典字段近似，我们详细分析了在弱且强烈的扰动状态下产生的密度波的性能。在前一种情况下，可以用流体动力或无碰撞声音来描述密度激发，但系统的强烈干扰会导致质上不同的响应。我们将观察到的结构确定为准糖浆，并发现其内部复杂性对于强扰动情况。对于这种状态，quasisolitons随着时间的流逝而闯入涡旋对，最终达到平衡状态。我们发现这种状态的特征是仅在时间平均数量的相反电荷涡旋和出现准较长范围的对成对上波动，如berezinskii-kosterlitz- thouless（bkt）相。
We theoretically study the sound propagation in a two-dimensional weakly interacting uniform Bose gas. Using the classical fields approximation we analyze in detail the properties of density waves generated both in a weak and strong perturbation regimes. While in the former case density excitations can be described in terms of hydrodynamic or collisionless sound, the strong disturbance of the system results in a qualitatively different response. We identify observed structures as quasisolitons and uncover their internal complexity for strong perturbation case. For this regime quasisolitons break into vortex pairs as time progresses, eventually reaching an equilibrium state. We find this state, characterized by only fluctuating in time averaged number of pairs of opposite charge vortices and by appearance of a quasi-long-range order, as the Berezinskii-Kosterlitz-Thouless (BKT) phase.
