  Simultaneous strong coherent pumping of the two transitions of a V-level atom
with very differentdecay rates has been predicted to create almost perfect
inversion on the narrower transition. Usingthe example of the blue and red
transitions in Strontium we show that for suitable operatingconditions the
corresponding resonant gain can be used to continuously operate a laser on
thenarrow transition. In particular, for a strong detuning of the pump field
with respect to the narrowtransition, coherent laser emission occurs close to
the bare atomic transition frequency exhibitingonly a negligible contribution
from coherent pump light scattered into the lasing mode.Calculations of the
cavity output spectrum show that the resulting laser linewidth can get
muchsmaller than the bandwidth of the pump light and even the natural linewidth
of the narrow atomictransition. Its frequency is closely tied to the atomic
transition frequency for properly chosen atomnumbers. Simulations including
atomic motionshow Doppler cooling on the strong transitionwith minor motion
heating on the lasing transition, so that continuous laser operation in
thepresence of a magneto-optical trap should be possible with current
experimental technology.
