All-Optical Switching in High Figure-of-Merit Materials

B. S. Wherrett

Features of optical bistability that are relevant to digital optical circuitry and possible architectures for such circuitry are described. Figures-of-merit are presented that indicate the material linear and nonlinear optical requirements for efficient optical switches.

Thomas Volz, Andreas Reinhard, Martin Winger +4 more

Ping Ma, Heinz Jäckel, G.L. Bona +1 more

In this paper, we propose and theoretically investigate an ultrafast, compact, and energy efficient all-optical switch (AOS) design based on a saturable absorbing cavity. The conceptual basis of the switch design is the material absorption saturation phenomenon. The optical cavity is used to enhance the light-matter interaction locally. As a result, the device dimension is substantially reduced. Numerical studies were carried out analytically using the temporal-coupled mode theory. Cavity structural parameters and material properties related to the switch design are discussed. The figure of merit of the switch performance in terms of the insertion loss, extinction ratio, and operating energy consumption are analyzed. Finally, as a specific practical application of the developed AOS, ultrahigh-speed optical time division multiplexing operations are demonstrated.

Li Li, Junqing Li, Xinlu Zhang +1 more

One of the major challenges in realizing practical all-optical switching devices is the need for strong and fast material nonlinearity. The use of resonance-enhanced nonlinear effects in optical cavities has been explored as a promising way to lower the switching power. This paper provides numerically investigation of resonator-enhanced Mach-Zehnder interferometer all-optical switch by employing a nonlinear ratio-variable coupler with the merits of easy fabrication and excellent nonlinear optical controllability. This performs nonlinear optical switching with advantages of hundreds tW low switching threshold, steady switch ON/OFF states and a wide wavelength range by combining the high nonlinearity of ring and adjustable coupling ratio of RVC. Resonator finesse is controllable by incident power with potential applications in controllable photonic devices. Some undesirable effects involving attenuation, group delay and partial coherence lead to increase of switching power and low extinction ratio. Optical bistability and instability do not limit practical applications in optical switch. A desired tradeoff between response time and switching power can be achieved by controlling finesse. Picosecond ultrafast all-optical switch is predicted.

H. Haug, L. Bányai