Revealing hidden antiferromagnetic correlations in doped Hubbard chains via string correlators
Revealing hidden antiferromagnetic correlations in doped Hubbard chains via string correlators
复制标题
DOI：
10.1126/science.aam8990
复制
发表时间：
2017-08-04
期刊：
影响因子：
56.9
通讯作者：
Gross, Christian
中科院分区：
文献类型：
--
作者：
Hilker, Timon A.;Salomon, Guillaume;Gross, Christian
拓扑相，如自旋-1链中的霍尔丹相，无法通过局部序参数表征。相反，可以使用非局部字符串顺序参数来显示它们的隐藏顺序。由于自旋-电荷分离现象，在掺杂一维晶格体系中也出现了类似的稀释磁相关性。在这里，我们报告了通过量子气体显微镜直接观察到这种隐藏的磁相关的空穴掺杂的超冷费米-哈伯德链。非局域自旋密度相关函数的测量揭示了一个隐藏的有限范围反铁磁秩序，这是自旋-电荷分离的直接结果。我们的技术可以直接测量非局部有序，可以很容易地扩展到更高的维度，以研究磁有序和密度波动之间的复杂相互作用。
Topological phases, like the Haldane phase in spin-1 chains, defy characterization through local order parameters. Instead, nonlocal string order parameters can be employed to reveal their hidden order. Similar dilutedmagnetic correlations appear in doped one-dimensional lattice systems owing to the phenomenon of spin-charge separation. Here we report on the direct observation of such hidden magnetic correlations via quantum gas microscopy of hole-doped ultracold Fermi-Hubbard chains. The measurement of nonlocal spin-density correlation functions reveals a hidden finite-range antiferromagnetic order, a direct consequence of spin-charge separation. Our technique, which measures nonlocal order directly, can be readily extended to higher dimensions to study the complex interplay between magnetic order and density fluctuations.