Population inversion for a single trapped two-level ion

Abstract

We investigate the conquest of sideband laser cooling and heating due to weak broad-band noise for a harmonically trapped two-level ion. The two opposite processes from an equilibrium distribution in the ion's quantum state of motion, i.e., the ground state of motion is depopulated. As another consequence we find population inversion between different manifolds of the ion's combined quantum states of internal electronic structure and external motion. This effect only results from the quantized treatment of the ion's motion.