Switching dynamics of optical bistable devices

Kuochou Tai, H. M. Gibbs, Jerome V. Moloney

Kuochou Tai, Jerry V. Moloney, Hyatt M. Gibbs

P. Wheatley, John Edwin Midwinter

We present a simple graphical analysis of the dynamic response of optical bistable devices. This technique shows qualitatively how the switching time of a device is affected by optical bias and signal powers and initial bias voltage, and may be used to optimise the switching time of a device.

Nasser N. Peyghambarian, H. M. Gibbs, Daniele Hulin +3 more

J.-Y. Bigot, A. Daunois, J. B. Grün

A model based on the heat diffusion equation is used to describe the switching dynamics in thermally induced optical bistable devices. In this model, energy is brought to the device by a cw holding light beam and by a light pulse. In this case, it is shown that switching times can be much faster than the thermal relaxation constant of the material. This model, applied to nonlinear ZnSe interference filters, explains the switching behavior recently observed.

Takasumi Tanabe, Akihiko Shinya, Eiichi Kuramochi +2 more

We review our recent progress on all-optical switching and bistability using ultrahigh-Q photonic crystal nanocavities. We also discuss all-optical logic gate operations. Because photonic crystal nanocavities can strongly confine photons in a small area for a long time, light can efficiently interact with dipoles. As a result, optical nonlinearities occur at a very low input. Optical nonlinearities are essential as regards all-optical switching and bistability, because they dynamically change such material properties as refractive index. We demonstrate all-optical switching at an operating energy of less than 100 fJ, and bistable operation at less than ~100 μW. In addition, these devices are small and so can operate at a reasonably high speed (~100 ps).