Light Amplification and Attenuation in Stratified Structures with Complex Refractive Index
We report a new kind of laser threshold resonance in electromagnetic wave propagation inside a layered medium. Specifically, for large values of the gain coefficient, the wave interaction with only the first few lattice interfaces results in transmission and reflection values much greater than unity. We also show that the duality phenomenon between losses and gains on the field amplitude decay is due to the existence of counter-propagating waves on reflection from the layer interfaces.
KeywordsReflection Coefficient Transmission Coefficient Pass Band Laser Threshold Complex Refractive Index
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