Synopsis: A Solid Look-Alike

A cold gas consisting of laser-trapped ions interacting with neutral atoms could be an ideal simulator of a solid.
Synopsis figure
U. Bissbort et al., Phys. Rev. Lett. (2013)

The physics of complex solids—such as superconductors, multiferroics, and compounds that exhibit colossal magnetoresistance—is often too difficult to tackle with theory or numerical analysis. Building a device that behaves exactly like a solid may instead be a better strategy for modeling these materials. For example, recent research has demonstrated that cold atoms trapped by lasers and arranged in “artificial lattices” can emulate the properties of solids. Now, in Physical Review Letters, theorists propose a combination of ionic and neutral gases that could be the ideal quantum simulator for solids in which electrons interact strongly with lattice vibrations.

Ulf Bissbort at the Institute for Theoretical Physics in Frankfurt, Germany, and his colleagues analyze a system consisting of a one-dimensional chain of laser-trapped ions, interacting with a surrounding cloud of neutral fermionic atoms. Their analysis shows that the two species would play the role of a solid’s atoms and electrons, respectively. What makes the scheme much closer to a real solid than previous cold-atom simulators is the interaction between the electronlike neutral atoms and the ions: the movement of the neutral atoms can induce vibrations of the ions around their equilibrium positions (and vice versa)—an interaction that mimics electron-phonon coupling in a natural solid.

The authors show that the system displays an interesting effect similar to that found in solids, called the Peierls instability: when cooled below a certain temperature, an equispaced chain of atoms with one electron per atom can distort and form dimers and, as a consequence, turn from a metal into an insulator. – Matteo Rini


More Announcements »

Subject Areas

Atomic and Molecular PhysicsStrongly Correlated Materials

Previous Synopsis

Next Synopsis

Particles and Fields

Spotlight on Photon-Photon Scattering

Read More »

Related Articles

Viewpoint: Cool Physics with Warm Ions
Atomic and Molecular Physics

Viewpoint: Cool Physics with Warm Ions

Ultrafast laser pulses can be used to control and characterize the quantum motion of a single trapped ion over 5 orders of magnitude in temperature. Read More »

Synopsis: The Quantum Hall Effect Leaves Flatland
Atomic and Molecular Physics

Synopsis: The Quantum Hall Effect Leaves Flatland

Cold atoms in an optical lattice with a synthetic extra dimension could be used to see the 4D version of the quantum Hall effect.   Read More »

Viewpoint: Emerging Quantum Order in an Expanding Gas
Condensed Matter Physics

Viewpoint: Emerging Quantum Order in an Expanding Gas

The spontaneous emergence of long-range quantum order, normally the preserve of low-temperature equilibrium states, has been observed in an expanding cloud of potassium atoms. Read More »

More Articles