Fractional charge and emergent mass hierarchy in diagonal two-leg t–J cylinders

Here, we define a class of "diagonal" t − J ladders rotated by π / 4 relative to the canonical lattice directions of the square lattice, and study it using density matrix renormalization group. Here, we focus on the two-leg cylinder with a doped hole concentration near x = (1/4) . At exactly x = (1/4), the system forms a period 4 charge density wave and exhibits spin-charge separation. Slightly away from (1/4) doping, we observe several topologically distinct types of solitons with well-defined fractionalized quantum numbers. Remarkably, given the absence of any obvious small parameter, the effective masses of the emergent solitons differ by several orders of magnitude.