Schäfer Frank, Bastarrachea-Magnani Miguel A, Lode Axel U J, de Parny Laurent de Forges, Buchleitner Andreas
Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Straße 3, D-79104 Freiburg, Germany.
Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
Entropy (Basel). 2020 Mar 26;22(4):382. doi: 10.3390/e22040382.
We examine the spectral structure and many-body dynamics of two and three repulsively interacting bosons trapped in a one-dimensional double-well, for variable barrier height, inter-particle interaction strength, and initial conditions. By exact diagonalization of the many-particle Hamiltonian, we specifically explore the dynamical behavior of the particles launched either at the single-particle ground state or saddle-point energy, in a time-independent potential. We complement these results by a characterization of the cross-over from diabatic to quasi-adiabatic evolution under finite-time switching of the potential barrier, via the associated time evolution of a single particle's von Neumann entropy. This is achieved with the help of the multiconfigurational time-dependent Hartree method for indistinguishable particles (MCTDH-X)-which also allows us to extrapolate our results for increasing particle numbers.
我们研究了一维双阱中两个和三个相互排斥作用的玻色子的光谱结构和多体动力学，研究对象包括可变的势垒高度、粒子间相互作用强度以及初始条件。通过对多粒子哈密顿量进行精确对角化，我们具体探究了在与时间无关的势场中，从单粒子基态或鞍点能量出发的粒子的动力学行为。我们通过单粒子冯·诺依曼熵的相关时间演化，对势垒在有限时间切换下从非绝热到准绝热演化的转变进行了刻画，以此补充上述结果。这借助于用于不可区分粒子的多组态含时哈特里方法（MCTDH-X）得以实现，该方法还使我们能够外推粒子数增加时的结果。
