Vectoral air lasing with arbitrary azimuthal angle

We demonstrate the generation of nitrogen ions lasing at 391.4 nm of cylindrical vector polarization with an arbitrary azimuthal angle pumped by a femtosecond vector pulse. Moreover, with the injection of an external seed pulse of linear polarization, the significantly amplified lasing emission retains the vector polarization property of the pump pulse. We attributed this transfer of the vectoral polarization of the pump to the self-seeded and externally seeded lasing to the anisotropy of the optical gain due to the permanent alignment of the nitrogen cations by the intense pump pulse, with the observations well reproduced by the simulations. Our method provides a simple scheme for the generation of vectorial air lasing and sheds new insights into the polarization effect in the air lasing process.