Hot carriers generated by plasmons: where are they are generated and where do they go from there?

A physically transparent unified theory of optically and plasmon induced hot carrier generation in metals is developed with all the relevant mechanisms included. Analytical expressions that estimate the carrier generation rates, their locations, energy and direction of motion are obtained. Among four mechanisms considered: interband absorption, phonon and defect assisted absorption, electron electron scattering assisted absorption, and surface collision assisted absorption (Landau damping), it is the last one that generates hot carriers which are most useful for practical applications in photo detection and photo catalysis.