The design of an optical triode.

Under the action of pump light, a conventional photonic crystal can be turned into a functional photonic crystal. In the paper, we have designed an optical triode with a one-dimensional functional photonic crystal, and analyzed the effect of period number, medium thickness, refractive index, incident angle, the irradiation frequency and the intensity of the pump light on the optical triode magnification. We obtain some valuable results, which shall help to optimize the design of optical triodes.

Electromagnetically induced grating based on the giant Kerr nonlinearity controlled by spontaneously generated coherence.

We propose a scheme for realizing electromagnetically induced grating via the giant Kerr nonlinearity in a coherently driven four-level system with spontaneously generated coherence. In the presence of spontaneously generated coherence, Kerr nonlinearity can be enhanced with vanishing linear absorption. Thus, with a standing-wave coupling field, one can achieve a pure absorption grating, which leads the probe field to gather the zero-order direction when the detuning of the coupling field is on resonance. Moreover, we can obtain a pure phase grating, which diffracts a weak probe light into the first-order direction and the second-order direction when the detuning of the coupling field is off resonance.