A single beam optical trapping system is used to trap and rotate silica and vaterite microspheres in high vacuum.Large vaterite microspheres with diameters up to 15 m are fabricated with multi-stage precipitation reactionsand are rotated in the trap through the transfer of spin angular momentum from the photons in the trappingbeam to the spheres. An electro-optic modulator is used to vary the polarization of the trapping beam, allowingfor control over the rotation with damping times on the order of a day and with rotation frequencies up to 10MHz for 10 μm diameter spheres. While highly birefringent spheres are successfully trapped at moderate vacuumpressures (≥10~（-2） mbar), poor reproducibility is observed for trapping spheres in high vacuum. This trappingbehavior is found to be independent of the morphology, birefringence, and monodispercity of the spheres.
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