We present an experimental and theoretical study of the response of a dipolar supersolid to a Bragg excitation at high-energy defined by the impulse approximation regime. We experimentally observe a continuous reduction of the response when tuning the contact interaction from an ordinary Bose-Einstein condensate to a supersolid state and ultimately to an incoherent array of droplets. Already in the supersolid regime, the observed reduction is faster than the one theoretically predicted by the Bogoliubov–de Gennes theory. By comparing experiments and theories, we are able to attribute this discrepancy to the presence of coherent phase dynamics induced by the crossing of the phase transition. The phase variations are found to change character along the phase diagram and become predominantly incoherent only when reaching the incoherent-droplet regime.

中文翻译：

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在自由粒子状态下，从玻色-爱因斯坦凝聚态到超固体的相变过程中超冷偶极气体的布拉格散射

我们提出了偶极超固体对脉冲近似机制定义的高能量布拉格激发的响应的实验和理论研究。我们通过实验观察到，当将接触相互作用从普通玻色-爱因斯坦凝聚物调整为超固态并最终调整为不连贯的液滴阵列时，响应会持续降低。已经在超固体状态下，观察到的还原速度比 Bogoliubov-de Gennes 理论理论预测的还原速度更快。通过比较实验和理论，我们能够将这种差异归因于相变交叉引起的相干相动力学的存在。发现相位变化沿相图改变特征，并且仅在达到非相干液滴状态时才变得主要是非相干的。