  Optical rotation is experimentally demonstrated in a semiconductor-based
three-dimensional chiral photonic crystal (PhC) at a telecommunication
wavelength. We design a rotationally-stacked woodpile PhC structure, where
neighboring layers are rotated by 45 degrees and four layers construct a single
helical unit. The mirror-asymmetric PhC made from GaAs with sub-micron
periodicity is fabricated by a micro-manipulation technique. The linearly
polarized light incident on the structure undergoes optical rotation during
transmission. The obtained results show good agreement with numerical
simulations. The measurement demonstrates the largest optical rotation angle as
large as 23 degrees at 1300 nm wavelength for a single helical unit.
