Orbital angular momentum (OAM) of optical vortex can twist azo-polymers to form a micron-scale chiral surface relief, reflecting the helical wavefront of the irradiated optical vortex beam, with the aid of spin angular momentum (SAM). In this work, we present a new approach for light induced chiral surface relief formation, in which chiral surface reliefs of azopolymers with multiple arms are formed by the irradiation of temporally rotating petal beams without OAM, but assisted by the SAM associated with circular polarization. Also, we demonstrate the orientation control of the fabricated multiple-armed chiral surface reliefs in azo-polymers by properly controlling the exposure time.
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