Tunable magnetic order in chiral coupled spin chains

We obtain the ground-state phase diagram of two spin chains consisting in a set of two-level systems asymmetrically coupled to an XX chain through a chiral interaction. The interaction is parametrized by its magnitude and an angle defined by the relative orientation of the spins in different chains. From the entanglement spectrum, we identify the critical lines separating distinct magnetically ordered phases, with the interaction angle able to shift or fully suppress the transition. By increasing the coupling strength, the system is driven through a quantum phase transition, leading to the formation of two types of in-plane antiferromagnetic stripes. The interaction strength sets stripe formation, while the angle controls the spins' orientations. The chiral interaction also induces a nontrivial finite vector spin chirality with opposite orientation on the chains. We show that the vector spin chirality emerges smoothly from the decoupled limit and occurs for angles different from zero and <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mrow> <a:mi>π</a:mi> <a:mo>/</a:mo> <a:mn>2</a:mn> </a:mrow> </a:math> , where collinear order is favored instead.