Observations of trapped ions phase transition processes

We directly observed laser-cooled $^{174}Yb^{+}$ ions confined in 4-rod Ion trap to study ions crystalline phase, and images of them taken by EM-CCD were used to characterize the structural phase of trapped ions and calculate temperature of each ion. With a variety of perturbations in the beginning, different structural phase transition processes were detected by continuously taking pictures of ions in the experiment. The experiments results are in good agreement with theoretically simulation that show symmetrical and partial temperature-driven structural phase transition for trapped ion crystal and help us understand ions melting phenomenon to increase ions lifetimes in the future.