For a Nd:YAG laser there are four pump levels located at 1.00 eV, 1.24 eV, 2.40 eV, and 2.54 eV. The 1.00 eV level is the ground state for the laser.
(a) What is shortest possible pump wavelength (in nanometers) that could be used to populate any of the excited energy levels?
(b) Knowing that a Nd:YAG laser emits photons of wavelength 1064 nm, determine the highest quantum efficiency possible associated with lasing between one of the pump levels and the ground level. The quantum efficiency is defined as the ratio of the energy of the laser photon to the energy of the pump photon.