Temporal behavior of population densities of V atoms in an optically pumped V vapor laser

The time variation of population densities of V atoms in absorption levels pertinent to an optically pumped atomic V vapor laser is studied experimentally. V vapor is generated from a V metal by irradiation of a pulsed Nd:YAG (λ=1.06 μm) laser of 2 J/pulse energy and 1.4 ms pulse duration. The population densities of the ground‐state and excited‐state (E∼2400 cm−1) V atoms have been measured by the interferometric method, and the temperature in the vapor is estimated from these populations. It has been experimentally observed that the populations of the ground state and the excited state are about 1×1014/cm3 and 4×1013/cm3, respectively. The temperature in the vapor increased from about 1800 to 4000 K with time during the YAG laser irradiation.