Acousto-optic bistable generator (A)

Ussr Uni

Hubert Jerominek, J.Y.D. Pomerleau, Réal Tremblay +1 more

K. D. A. Sabóia, Alex Sander Barros Queiroz, Francisco Tiago Lima +3 more

In this paper we report for the first time the presence of bistability in an acoustic-optic tunable filter (AOTF) operating with ultrashort (2 ps) optical light pulses. The results for the study of bistability has shown the dependence of the hysteresis curve with the product of the coupling constant (κ) by the length of the device (ξL) and the conversion power-coupling constant factor (G). The range of bistability varies significantly with both G and with κξL parameters. The variation of κξL directly increases the size of the range of bistability hysteresis while the increase in G causes the bistability to occur at low powers. The phenomenon of optical bistability (OB) is the object of increasing interest due to its possibilities for important device applications. A bistable device is a device with a capability to generate two different outputs for a given input and the physical requirements for this are an intensity-dependence refractive index and an optical feedback mechanism.

Mark D. McNeill, Ting‐Chung Poon

Previous research with acousto-optic hybrid optical/electronic (HOE) bistable devices has been directed towards operation in the first Bragg regime.1 We have demonstrated several simulations and experiments to study a HOE bistable system in the second Bragg regime. In this bistable system, the acousto-optic device operates in the second order with the light incident at twice the Bragg angle. To achieve optical bistability, the second order diffracted light is detected by a photodetector, amplified with a linear amplifier, summed with a bias voltage, and feedback to the acousto-optic device. The operation of the acousto-optic device can be explained by a set of coupled differential equations. Likewise, the feedback loop can be modeled with a feedback equation. The simultaneous solution of these equations provided our theoretical model. In this talk, we will compare theoretical and experimental results, as well as compare first order and second order operation.

Yongda Li, Ke Shen, Liqun Huang +1 more

A theoretical investigation has been undertaken to study the amplification of small-signal by an acousto-optic bistable system operating in the Bragg regime. Numerical solutions of the difference-differential equation show strong coupling between small-signal and the optical bistable system. Near the bifurcation point an amplification of 23 is obtained. computed time plots for different parameters and the beat characteristic curve are given.

S. L. McCall, H. M. Gibbs, Thirumalai Venkatesan