Hartke Thomas, Oreg Botond, Jia Ningyuan, Zwierlein Martin
Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Phys Rev Lett. 2020 Sep 11;125(11):113601. doi: 10.1103/PhysRevLett.125.113601.
We report on the single atom and single site-resolved detection of the total density in a cold atom realization of the 2D Fermi-Hubbard model. Fluorescence imaging of doublons is achieved by splitting each lattice site into a double well, thereby separating atom pairs. Full density readout yields a direct measurement of the equation of state, including direct thermometry via the fluctuation-dissipation theorem. Site-resolved density correlations reveal the Pauli hole at low filling, and strong doublon-hole correlations near half filling. These are shown to account for the difference between local and nonlocal density fluctuations in the Mott insulator. Our technique enables the study of atom-resolved charge transport in the Fermi-Hubbard model, the site-resolved observation of molecules, and the creation of bilayer Fermi-Hubbard systems.
我们报道了在二维费米-哈伯德模型的冷原子实现中对总密度的单原子和单格点分辨检测。通过将每个晶格位点分裂成一个双阱来实现对双占据子的荧光成像，从而分离原子对。全密度读出可直接测量状态方程，包括通过涨落耗散定理进行直接温度测量。格点分辨的密度关联揭示了低填充时的泡利空穴以及接近半填充时的强双占据子-空穴关联。结果表明，这些关联解释了莫特绝缘体中局域和非局域密度涨落之间的差异。我们的技术能够研究费米-哈伯德模型中原子分辨的电荷输运、分子的格点分辨观测以及双层费米-哈伯德系统的创建。
