A Wigner crystal formed with trapped ions can undergo a structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be driven solely by a change in the system's temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.A Wigner crystal formed with trapped ions can undergo a structural phase transition, which is determined only by the mechanical conditions on a classical level. Instead of this classical result, we show that through consideration of quantum and thermal fluctuation, a structural phase transition can be driven solely by a change in the system's temperature. We determine a finite-temperature phase diagram for trapped ions using the renormalization group method and the path integral formalism, and propose an experimental scheme to observe the predicted temperature-driven structural phase transition, which is well within the reach of the current ion trap technology.

arXiv:1009.0089Physical Review LettersDec 29, 201028 citations

Ion-crystal demonstration of a temperature-driven structural phase transition

Ji Li, L.-L. Yan, Liang Chen +5 more

Thermal fluctuation usually damages observations in physical systems. But here we demonstrate a unique contribution made by thermal fluctuation, that is, our observation of linear-zigzag phase transitions induced solely by temperature of the $^{40}\mathrm{Ca}^{+}$ ion crystals in a surface-electrode trap. In contrast to the previously observed counterparts based on change in the mechanical equilibrium conditions of the ions, our presented structural phase transition occurs due to controllable influence of thermal fluctuation. The ions' temperature is well controlled by tuning the cooling laser and the experimental observation could be fully understood by classical Langevin equation in addition to the effects from thermal fluctuation. Our experimental investigation indicates the possibility of the positive role thermal fluctuation played in the thermodynamic process at the atomic level, which might bridge the thermodynamics from the macroscopic domain to the quantum regime.Thermal fluctuation usually damages observations in physical systems. But here we demonstrate a unique contribution made by thermal fluctuation, that is, our observation of linear-zigzag phase transitions induced solely by temperature of the $^{40}\mathrm{Ca}^{+}$ ion crystals in a surface-electrode trap. In contrast to the previously observed counterparts based on change in the mechanical equilibrium conditions of the ions, our presented structural phase transition occurs due to controllable influence of thermal fluctuation. The ions' temperature is well controlled by tuning the cooling laser and the experimental observation could be fully understood by classical Langevin equation in addition to the effects from thermal fluctuation. Our experimental investigation indicates the possibility of the positive role thermal fluctuation played in the thermodynamic process at the atomic level, which might bridge the thermodynamics from the macroscopic domain to the quantum regime.

arXiv:1812.04347Physical Review AJun 5, 201914 citations

Structure and Dynamics of Trapped Ions

Joel H. Parks

CRC Press eBooksNov 11, 20092 citations

Quantum phase transitions in an ion trap

Milburn

Quantum Electronics and Laser Science ConferenceJan 1, 20000 citations

^{40}\mathrm{Ca}^{+}

ion crystals in a surface-electrode trap. In contrast to the previously observed counterparts based on change in the mechanical equilibrium conditions of the ions, our presented structural phase transition occurs due to controllable influence of thermal fluctuation. The ions' temperature is well controlled by tuning the cooling laser and the experimental observation could be fully understood by classical Langevin equation in addition to the effects from thermal fluctuation. Our experimental investigation indicates the possibility of the positive role thermal fluctuation played in the thermodynamic process at the atomic level, which might bridge the thermodynamics from the macroscopic domain to the quantum regime.