I How Does Superradiance Enhance Radiation Intensity?

[TheCanadian]

I was reading through a paper and it says that super radiance enhances radiation intensity. That this can be understood by the fact that when the distance between neighboring atoms is much smaller than the wavelength of radiation, the photon emitted by one atom is seen to be in phase by neighboring atoms and can bring about the emission of a new photon of the same mode and the same direction as the initial photon. I just don't quite understand how this increases intensity. Wouldn't that initial photon used to eject the new photon be lost in the process of exciting it? I believe in this case, some of the atoms already have the electrons in an excited state, while the others are in the ground state. But nonetheless, how does that one photon actually eject another photon without being consumed in the process itself?

 

[Andy Resnick]

My understanding of superradiance is that it's a coherent interaction between the atoms and external field, similar to lasing and stimulated emission.