Department of Physics, University of California, Santa Barbara, California 93106, USA.
Phys Rev Lett. 2009 Oct 2;103(14):140403. doi: 10.1103/PhysRevLett.103.140403. Epub 2009 Sep 29.
Inspired by experiments on Bose-Einstein condensates in optical lattices, we study the quantum evolution of dark soliton initial conditions in the context of the Bose-Hubbard Hamiltonian. An extensive set of quantum measures is utilized in our analysis, including von Neumann and generalized quantum entropies, quantum depletion, and the pair correlation function. We find that quantum effects cause the soliton to fill in. Moreover, soliton-soliton collisions become inelastic, in strong contrast to the predictions of mean-field theory. These features show that the lifetime and collision properties of dark solitons in optical lattices provide clear signals of quantum effects.
受光学晶格中玻色-爱因斯坦凝聚实验的启发，我们在玻色-哈伯德哈密顿量的框架下研究了暗孤子初始条件的量子演化。在我们的分析中，利用了广泛的量子度量，包括冯·诺依曼和广义量子熵、量子耗散和对关联函数。我们发现量子效应导致孤子填充。此外，孤子-孤子碰撞变得非弹性，与平均场理论的预测形成鲜明对比。这些特征表明，光学晶格中暗孤子的寿命和碰撞特性提供了量子效应的明显信号。
