Photoassociation of ultracold long-range polyatomic molecules

We explore the feasibility of optically forming long-range tetratomic and larger polyatomic molecules in their ground electronic state from ultracold pairs polar aligned by external fields. Depending on relative orientation interacting diatomic molecules, we find that a can be formed either as weakly bound complex very extended halo or pure molecule composed collinear nearly-collinear molecules. The latter is novel type comprised two at long intermolecular range predicted to stable cold regimes. Our numerical studies were conducted for KRb RbCs, resulting production (KRb)$_2$ (RbCs)$_2$ complexes, respectively. Based universal properties interactions between identify triatomic linear with favorable ratio dipole quadrupole moments which apporach could generalized form