Li Sheng-Chang, Ye Chong
School of Science, Xi'an Jiaotong University, 710049 Xi'an, China.
Graduate School, China Academy of Engineering Physics, 100088 Beijing, China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Dec;92(6):062147. doi: 10.1103/PhysRevE.92.062147. Epub 2015 Dec 29.
We numerically demonstrate the dynamic stabilization of a strongly interacting many-body bosonic system which can be realized by coupled ultracold atom-molecule gases. The system is initialized to an unstable equilibrium state corresponding to a saddle point in the classical phase space, where subsequent free evolution gives rise to atom-molecule conversion. To control and stabilize the system, periodic modulation is applied that suddenly shifts the relative phase between the atomic and the molecular modes and limits their further interconversion. The stability diagram for the range of modulation amplitudes and periods that stabilize the dynamics is given. The validity of the phase diagram obtained from the time-average calculation is discussed by using the orbit tracking method, and the difference in contrast with the maximum absolute deviation analysis is shown as well. A brief quantum analysis shows that quantum fluctuations can put serious limitations on the applicability of the mean-field results.
我们通过数值方法证明了一个强相互作用多体玻色子系统的动态稳定,该系统可由耦合的超冷原子 - 分子气体实现。系统初始化为对应于经典相空间中鞍点的不稳定平衡态,在此处随后的自由演化会导致原子 - 分子转换。为了控制和稳定该系统,施加了周期性调制,该调制会突然改变原子和分子模式之间的相对相位并限制它们的进一步相互转换。给出了稳定动力学的调制幅度和周期范围内的稳定性图。通过使用轨道跟踪方法讨论了从时间平均计算获得的相图的有效性,并且还展示了与最大绝对偏差分析相比的差异。一个简短的量子分析表明,量子涨落会对平均场结果的适用性造成严重限制。