Grusdt Fabian, Pollet Lode
Department of Physics and Arnold Sommerfeld Center for Theoretical Physics (ASC), Ludwig-Maximilians-Universität München, Theresienstr. 37, München D-80333, Germany.
Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, D-80799 München, Germany.
Phys Rev Lett. 2020 Dec 18;125(25):256401. doi: 10.1103/PhysRevLett.125.256401.
We study the interplay of spin and charge degrees of freedom in a doped Ising antiferromagnet, where the motion of charges is restricted to one dimension. The phase diagram of this mixed-dimensional t-J_{z} model can be understood in terms of spinless chargons coupled to a Z_{2} lattice gauge field. The antiferromagnetic couplings give rise to interactions between Z_{2} electric field lines which, in turn, lead to a robust stripe phase at low temperatures. At higher temperatures, a confined meson-gas phase is found for low doping whereas at higher doping values, a robust deconfined chargon-gas phase is seen, which features hidden antiferromagnetic order. We confirm these phases in quantum Monte Carlo simulations. Our model can be implemented and its phases detected with existing technology in ultracold atom experiments. The critical temperature for stripe formation with a sufficiently high hole concentration is around the spin-exchange energy J_{z}, i.e., well within reach of current experiments.
我们研究了掺杂的伊辛反铁磁体中自旋与电荷自由度之间的相互作用,其中电荷运动被限制在一维。这个混合维度的t-Jₓ模型的相图可以通过与Z₂晶格规范场耦合的无自旋荷子来理解。反铁磁耦合导致Z₂电场线之间的相互作用,进而在低温下产生一个稳定的条纹相。在较高温度下,对于低掺杂发现了一个禁闭的介子气 相,而在较高掺杂值时,出现了一个稳定的解禁荷子气相,其具有隐藏的反铁磁序。我们在量子蒙特卡罗模拟中证实了这些相。我们的模型可以用现有技术在超冷原子实验中实现并检测其相。在足够高的空穴浓度下形成条纹的临界温度约为自旋交换能Jₓ,即在当前实验可达到的范围内。