Low Power Nonlinear Active Devices Based on Intrinsic Metal Nonlinearities

In this paper, we report a novel low-power nonlinear plasmonic nanoswitch mainly based on optical nonlinearity of centro-symmetric metals. We consider metal nonlinear terms including electrical and magnetic parts of Lorentz force and convective effect, due to the free electron mobility and Lorentz oscillator for bound electrons. We use hydrodynamic model for free electrons of metal to describe nonlinear terms that play more significant role in the second and third harmonic generation processes. We study the impact of each individual term. Our simulation results show that the convective term is much more effective than the others. We simulate the second harmonic generation of 2-D nanopillar and plasmonic switch by the 2-D finite difference time domain method. The required powers for exciting the intrinsic metal nonlinearities due to the free and bound electrons are less than those of other kinds of nonlinearities such as Kerr effect in dielectrics. In our nanoswitch, fundamental frequency as a pump signal controls each output ports and switching performance.