The system of a trapped ion translationally excited by a blue-detuned
near-resonant laser, sometimes described as an instance of a phonon laser, has
recently received attention as interesting in its own right and for its
application to non-destructive readout of internal states of non-fluorescing
ions. Previous theoretical work has been limited to cases of two-level ions.
Here, we perform simulations to study the dynamics of a phonon laser involving
the Λ-type ^{138}\mbox{Ba}^{+} ion, in which coherent population
trapping effects lead to different behavior than in the previously studied
cases. We also explore optimization of the laser parameters to maximize
amplification gain and signal-to-noise ratio for internal state readout