Synopsis: Superposed in a Crystal

Spin-dependent forces create quantum superpositions of different structures of a trapped ion crystal.
Synopsis figure
J. D. Baltrusch et al., Phys. Rev. A (2011)

In quantum mechanics, a system with distinct eigenstates can exist in a superposition of two or more states with specific probability amplitudes. The creation and manipulation of these superpositions is central to quantum computing. Efforts to experimentally realize quantum superpositions of macroscopic objects that are larger than an electron or a photon have generally focused on controlling their quantum dynamics and their interaction with the environment. Strings of trapped ions, an interesting example of many-body objects that can behave quantum mechanically, have attracted attention due to their remarkable contribution to quantum technologies, such as their use in the realization of quantum simulators and quantum teleportation protocols.

In an article in Physical Review A, Jens Baltrusch at Saarland University, Germany, and his colleagues report theoretical work on the dynamics of two different structures—linear and zigzag—of a trapped ion crystal. Starting out with a chain of ions at rest in a regime close to its structural phase transition, they excite—with spin-dependent trapping—a particular ion of the crystal into a superposition of metastable electronic states. Coulomb forces then modify the motions of the other ions in relation to the state of the chosen one, producing a state in which all the ions are entangled. This state is manifested as a superposition of different crystalline structures—a so-called cat state—and, according to the authors, should be observable with interferometry. – Jihane Mimih


More Announcements »

Subject Areas

Quantum InformationMesoscopicsQuantum Physics

Previous Synopsis

Next Synopsis


Pnictide Gap Symmetry

Read More »

Related Articles

Synopsis: Chilled Cavity Reaches New Level of Quiet

Synopsis: Chilled Cavity Reaches New Level of Quiet

A crystal cavity for light and sound has been chilled close to its motional ground state. Read More »

Synopsis: Bright Twins

Synopsis: Bright Twins

An optical-fiber scheme generates a bright “twin beam”—a pair of quantum-correlated beams that could be used in high-precision metrology. Read More »

Viewpoint: Wiring Up Superconducting Qubits
Quantum Physics

Viewpoint: Wiring Up Superconducting Qubits

A qubit made of a semiconducting nanowire sandwiched between two superconductors could simplify the design of quantum information processing architectures. Read More »

More Articles