论文标题
关于时空晶体的长期稳定性
On the long-term stability of space-time crystals
论文作者
论文摘要
我们研究了超流体玻色气体中的时空晶体。使用良好控制的周期性驱动器，我们在系统中仅激发了一种晶体模式，可以在驱动器的旋转框架中准确建模。使用全息成像，我们在很长的时间内观察到晶体的稳定性，并在时空和时间上显示其结构的稳健性。通过在哈密顿量中引入四阶术语，我们表明晶体以固定数量的量子稳定。将模型的结果与实验数据进行了比较，并显示出良好的一致性，并与少数免费参数进行了比较。结果产生了晶体长期稳定性的见解，这只能通过实验中扩展控制的组合和模型的几乎AB-Initio特征获得。从该模型中，我们得出了系统的相图，将来可以利用该模型，以更详细地研究这种新物质状态的相变。
We investigate a space-time crystal in a superfluid Bose gas. Using a well-controlled periodic drive we excite only one crystalline mode in the system, which can be accurately modeled in the rotating frame of the drive. Using holographic imaging we observe the stability of the crystal over an extended period of time and show the robustness of its structure in both space and time. By introducing a fourth-order term in the Hamiltonian we show that the crystal stabilizes at a fixed number of quanta. The results of the model are compared to the experimental data and show good agreement, with a small number of free parameters. The results yield insights in the long-term stability of the crystal, which can only be obtained by the combination of the extended control in the experiment and the nearly ab-initio character of the model. From the model we derive a phase diagram of the system, which can be exploited in the future to study the phase transitions for this new state of matter in even more detail.
