Related Experiment Video
Updated: May 16, 2026

Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps
Published on: August 17, 2017
Space-time crystals of trapped ions
Tongcang Li1, Zhe-Xuan Gong, Zhang-Qi Yin
1NSF Nanoscale Science and Engineering Center, 3112 Etcheverry Hall, University of California, Berkeley, California 94720, USA.
Researchers propose a novel space-time crystal using trapped ions. This crystal exhibits persistent rotation, offering new avenues for exploring quantum physics and material properties.
Area of Science:
- Quantum physics
- Condensed matter physics
- Many-body physics
Background:
- Spontaneous symmetry breaking is a key mechanism in forming spatial and time crystals.
- Trapped ions offer a controllable platform for studying quantum phenomena.
Purpose of the Study:
- To propose and experimentally realize a novel space-time crystal composed of trapped ions.
- To explore the underlying physics of persistent rotation in ion crystals.
- To investigate the robustness and potential applications of these space-time crystals.
Main Methods:
- Confining ions in a ring-shaped potential with a static magnetic field.
- Utilizing Coulomb repulsion to form a spatial ring crystal.
- Inducing persistent quantum rotation in the lowest energy state using fractional magnetic fluxes.
Main Results:
- Demonstrated the spontaneous formation of a spatial ring crystal of trapped ions.
- Achieved persistent quantum rotation of the ion crystal, establishing temporal order.
- Confirmed the robustness of the proposed space-time crystals for experimental observation.
- Analyzed the impact of finite temperatures on the persistent rotation.
Conclusions:
- The proposed trapped ion system successfully forms a space-time crystal.
- Persistent quantum rotation in ion crystals is a viable mechanism for creating temporal order.
- These space-time crystals are robust and experimentally accessible.
- This work opens new possibilities for exploring many-body physics and emergent properties of matter.
Related Concept Videos
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Unit Cells
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Mass Analyzers: Common Types
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Imperfections in Crystal Structure: Stoichiometric Point Defects

