Abstract
AbstractWhile engineered quantum systems are a general route to the manipulation of multipartite quantum states, access in a physical system to a continuous quantum phase transition under sufficient control offers the possibility of an intrinsic source of entangled states. To this end we realize the quantum version of the linear-zigzag structural transition for arrays of up to five ground state-cooled ions held in a linear Paul trap and we demonstrate several of the control requirements towards entangled-state interferometry near the critical point. Using in situ spectroscopy we probe the energy level structure and occupation of the soft mode associated with the structural transition, and show a stable critical point and majority ground state occupation crossing the transition. We resolve biases arising from trap electrode asymmetries that change the nature of the transition, show that they can be suppressed by varying the ion number, and demonstrate control of the transition bias using optical dipole forces.
Funder
Gouvernement du Canada | Natural Sciences and Engineering Research Council of Canada
China Scholarship Council
Publisher
Springer Science and Business Media LLC
Subject
Computational Theory and Mathematics,Computer Networks and Communications,Statistical and Nonlinear Physics,Computer Science (miscellaneous)
Reference52 articles.
1. Diedrich, F., Peik, E., Chen, J. M., Quint, W. & Walther, H. Observation of a phase transition of stored laser-cooled ions. Phys. Rev. Lett. 59, 2931–2934 (1987).
2. Wineland, D. J., Bergquist, J. C., Itano, W. M., Bollinger, J. J. & Manney, C. H. Atomic-ion Coulomb clusters in an ion trap. Phys. Rev. Lett. 59, 2935–2938 (1987).
3. Birkl, G., Kassner, S. & Walther, H. Multiple-shell structures of laser-cooled 24Mg+ ions in a quadrupole storage ring. Nature 357, 310–313 (1992).
4. Mitchell, T. B. et al. Direct observations of structural phase transitions in planar crystallized ion plasmas. Science 282, 1290–1293 (1998).
5. Major, F. G., Gheorghe, V. N. & Werth, G. Charged Particle Traps: Physics and Techniques of Charged Particle Field Confinement (Springer-Verlag, 2005).