A novel method for square pulse generation using nonlinear amplifying loop mirror

In this paper, we theoretically present a novel method applying nonlinear amplifying loop mirror to generate square pulse. From our analysis, the generated square pulse is steady and flat. We give the criteria for steady power and point out that there would be a stable region around the certain steady power. With the steady power given, the temporal width and other properties of square pulse will be determined. We also find that due to the steady power and stable region, the laser could give a multi-square-pulse output by adjusting the controlling light. An example of initially Gaussian pulse is discussed to support the idea. By adjusting transmission characteristics of the nonlinear amplifying loop mirror we will get different steady power, and then we can control power, temporal width and other properties of the generated square pulse by tuning the controlling light and choosing proper optical components. We also give a restriction for choosing optical components.