Mesoscopic spin-boson models of trapped ions

Trapped ions arranged in Coulomb crystals provide us with the elements to study the physics of a single spin coupled to a boson bath. In this work, we show that optical forces allow us to realize a variety of spin-boson models, depending on the crystal geometry and the laser configuration. We study in detail the ohmic case, which can be implemented by illuminating a single ion with a traveling wave. The mesoscopic character of the phonon bath in trapped ions induces effects such as the appearance of quantum revivals in the spin evolution.