Physics Department, Harvard University, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2011 Mar 18;106(11):115302. doi: 10.1103/PhysRevLett.106.115302. Epub 2011 Mar 16.
Nontrivial symmetry of order parameters is crucial in some of the most interesting quantum many-body states of ultracold atoms as well as condensed matter systems. Examples in cold atoms include p-wave Feshbach molecules and d-wave paired states of fermions that could be realized in optical lattices in the Hubbard regime. Identifying these states in experiments requires measurements of the relative phase of different components of the entangled pair wave function. We propose and discuss two schemes for such phase-sensitive measurements, based on two-particle interference revealed in atom-atom or atomic density correlations. Our schemes can also be used for relative phase measurements for nontrivial particle-hole order parameters, such as d-density wave order.
序参量的非平凡对称在超冷原子以及凝聚态系统的一些最有趣的量子多体态中至关重要。在冷原子中，例子包括 p 波 Feshbach 分子和费米子的 d 波配对态，这些态可以在 Hubbard 区的光晶格中实现。在实验中识别这些态需要测量纠缠对波函数不同分量的相对相位。我们提出并讨论了两种基于原子-原子或原子密度相关中揭示的双粒子干涉的相敏测量方案。我们的方案也可用于非平凡粒子-空穴序参量的相对相位测量，例如 d 密度波序参量。
