(a) A 3D rendering of the hybrid trap used to create an ensemble of trapped ions immersed in a laser-cooled buffer gas, as shown in the inset composite photograph. (b) Analytical heating and cooling rates for ions in a hybrid atom–ion trap. Three characteristic regimes exist for different relative heating and cooling strengths as parameterized by Ni and are characterized by the number and type of fixed points they exhibit. (c) Steady-state evolution of ion temperatures for different Ni and initializations as calculated by the MD simulation and analytical model. The left (right) pairs convey this evolution near the opening (closing) of the bifurcation at Ni=3 (Ni=26), where the number of steady-state temperatures go from one (two) to two (one). (d) Steady-state temperatures for different Ni and initializations as calculated by the MD simulation and analytical model. Error bars represent s.e. Red (blue)-shaded regions represent the ranges of ion temperatures before immersion for the hot (cold) initialization. Regimes I, II, and III are observed and indicated by differently shaded regions. The transitions between these regimes are marked by blue-sky bifurcations.