I would like to split light from a circularly polarized laser source into two beams. What happens when it passes through a cube beamsplitter – both non-polarizing and polarizing?

When circularly polarized laser light passes through a Polarizing Cube Beamsplitter, P-polarized light is transmitted while S-polarized light reflected. On the other hand, when circularly polarized light passes through a Non-polarizing Cube Beamsplitter, the reflected and transmitted components contain the same polarization characteristics of the source beam. Namely, both the reflected and the transmitted components will be circularly polarized.