基于金属膜上L形纳米孔的线偏振旋转器

n L-shaped nanohole in a gold film is proposed to realize linear polarization rotation of light at subwavelength scale and its optical properties are analyzed using the finite difference time domain method. The mechanism of the polarization rotation is based on the 180 degree phase retardation between two different resonant modes with orthogonal polarization directions in the L-shaped nanohole. The working wavelength of the polarization rotator can be tuned conveniently in the range of 735-1080 nm by varying the hole length.