We investigate the interaction between acoustic and optical signals in Bragg gratings. Using the multiple-scale method, we convert the optoacoustic coupled mode equations into a standard nonlinear Schrdinger equation. Thus, we obtain approximate solutions of the optoacoustic coupled mode equations, such as the single-soliton solutions and multiple-soliton solutions. Furthermore, we discuss the properties of slowing light of optoacoustic solitons and the interaction of two-soliton solutions.

Abstract. For the flow control over a backward-facing step, two types of right-angle-shaped plasma actuators are specially designed with the electrodes connected in series and parallel manner, respectively. And this paper deals with the special design electrodes for avoiding the limited effects from the interaction between the elelctrodes which will resist the main forward flow which is being accelerated. Through PIV measurements, the excitation effects of the two different connection manners of the electrodes are compared and analyzed. The experimental results indicate that the flow induced by the actuator in both connection manners is along 45°. The special design electrode connection manner can suppress the adverse effect caused by reverse discharge at a certain extent.