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arXiv · 1410.4630

Enhancement of Laser Power Efficiency by Control of Spatial Hole Burning Interactions

Li Ge·Omer Malik·Hakan E. Tureci
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Abstract

The laser is an out-of-equilibrium nonlinear wave system where the interplay of the cavity geometry and nonlinear wave interactions, mediated by the gain medium, determines the self-organized oscillation frequencies and the associated spatial field patterns. In the steady state, a constant energy flux flows through the laser from the pump to the far field, with the ratio of the total output power to the input power determining the power-efficiency. While nonlinear wave interactions have been modeled and well understood since the early days of laser theory, their impact on the power-efficiency of a laser system is poorly understood. Here, we show that spatial hole burning interactions generally decrease the power efficiency. We then demonstrate how spatial hole burning interactions can be controlled by a spatially tailored pump profile, thereby boosting the power-efficiency, in some cases by orders of magnitude.

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Li Ge, Omer Malik, Hakan E. Tureci. 2014-10-17. Enhancement of Laser Power Efficiency by Control of Spatial Hole Burning Interactions. https://doi.org/10.1038/nphoton.2014.244

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