AI 中文总结
研究半填充SU($N$)两腿费米子梯子中环流有序相，用低能方法发现相关非微扰对偶对称性，通过晶格对偶性揭示与传统相的关系，用微扰重整化群方法得出$N>2$时相关相在特定条件下稳定，并讨论了小掺杂影响。
AI 中文摘要
我们研究了半填充SU($N$)两腿费米子梯子中环流有序相的形成。采用低能方法，我们发现了与四种竞争序相关的非微扰对偶对称性。其中两种序对应于自发破缺时间反演对称性的环流有序相，描述了电荷电流以交错模式围绕晶格元胞或沿梯子对角线循环。通过晶格上存在的精确密度-电流对偶对称性，这些非传统相被证明与传统（电荷和键）密度波相是对偶的。从微扰重整化群方法，我们发现对于$N>2$，这些相在具有额外SU($N$)洪德相互作用的半填充SU($N$)两腿哈伯德梯子中是稳定的。还讨论了小掺杂对这些相的影响。
英文摘要
We investigate the formation of loop-current ordered phases in half-filled SU($N$) two-leg fermionic ladders. Using a low-energy approach, we uncover the existence of non-perturbative duality symmetries relating four competing orders. Two of these orders correspond to loop-current ordered phases that spontaneously break the time-reversal symmetry and describe charge currents circulating in a staggered pattern either around the plaquettes or along the diagonals of the ladder. These unconventional phases are shown to be dual to conventional (charge and bond) density-wave phases through an exact density-current duality symmetry existing on the lattice. From a perturbative renormalization group approach, we find that these phases for $N>2$ are stabilized in a half-filled SU($N$) two-leg Hubbard ladder with an additional SU($N$) Hund's interaction. The effect of a small doping on these phases is also discussed.
Comments19 pages, 7 figures
