论文标题
观察Lee-huang-yang流体
Observation of a Lee-Huang-Yang Fluid
论文作者
论文摘要
我们观察到在玻色网凝结物的混合物中观察到单极振荡，其中通常取消了通常的主要平均场相互作用。在这种情况下，该系统由下一阶Lee-huang-yang（Lhy）对基态能量进行校正，该校正描述了量子波动的影响。在实验上，通过控制限制在球形陷阱电位的$^{39} $ k旋转混合物中的原子数和相互作用强度来实现这种LHY流体。如Jørgensen等人最近提出的那样，我们测量单极振荡频率是LHY相互作用强度的函数。 [物理。莱特牧师。 121，173403（2018）]并与完整实验的模拟找到了极好的一致性，包括激发程序和非弹性损失。这证实了该系统及其集体行为最初由LHY相互作用支配。此外，发现单极振荡频率在围绕理想值的宽区域中所涉及的散射长度的变化稳定，从而证实了LHY相互作用的稳定作用。这些结果为使用LHY项在量子模拟实验中提供的非线性铺平了道路，并进行了LHY制度以外的研究。
We observe monopole oscillations in a mixture of Bose-Einstein condensates, where the usually dominant mean-field interactions are canceled. In this case, the system is governed by the next-order Lee-Huang-Yang (LHY) correction to the ground state energy, which describes the effect of quantum fluctuations. Experimentally such a LHY fluid is realized by controlling the atom numbers and interaction strengths in a $^{39}$K spin mixture confined in a spherical trap potential. We measure the monopole oscillation frequency as a function of the LHY interaction strength as proposed recently by Jørgensen et al. [Phys. Rev. Lett. 121, 173403 (2018)] and find excellent agreement with simulations of the complete experiment including the excitation procedure and inelastic losses. This confirms that the system and its collective behavior are initially dominated by LHY interactions. Moreover, the monopole oscillation frequency is found to be stable against variations of the involved scattering lengths in a broad region around the ideal values, confirming the stabilizing effect of the LHY interaction. These results pave the way for using the non-linearity provided by the LHY term in quantum simulation experiments and for investigations beyond the LHY regime.
