Physics Spotlight  
Atoms are like small magnets, so applying a magnetic force pushes them around, here, to the left (top left). Since these atoms repel each other, they cannot move if there are no empty sites (top middle). But the atomic “magnetic needles” are still free to move, with stronger magnets (red) diffusing to the left in the image, and weaker magnets (blue) having to make room and move to the right (bottom row). This so-called spin transport is resolved atom by atom in the cold atom quantum emulator. Images: courtesy of the researchers Atoms are like small magnets, so applying a magnetic force pushes them around, here, to the left (top left). Since these atoms repel each other, they cannot move if there are no empty sites (top middle). But the atomic “magnetic needles” are still free to move, with stronger magnets (red) diffusing to the left in the image, and weaker magnets (blue) having to make room and move to the right (bottom row). This so-called spin transport is resolved atom by atom in the cold atom quantum emulator. Images: courtesy of the researchers

Atoms stand in for electrons in system for probing high-temperature superconductors

Using new “quantum emulator,” physicists can observe individual atoms moving through these materials, and measure their speed.

Helen Knight | MIT News correspondent
December 6, 2018

High-temperature superconductors have the potential to transform everything from electricity transmission and power generation to transportation.

The materials, in which electron pairs travel without friction — meaning no energy is lost as they move — could dramatically improve the energy efficiency of electrical systems.

Understanding how electrons move through these complex materials could ultimately help researchers design superconductors that operate at room temperature, dramatically expanding their use.

However, despite decades of research, little is known about the complex interplay between the spin and charge of electrons within superconducting materials such as cuprates, or materials containing copper.

Now, in a paper published today in the journal Science, researchers at MIT have unveiled a new system in which ultracold atoms are used as a model for electrons within superconducting materials.

The researchers, led by Martin Zwierlein, the Thomas A. Frank Professor of Physics at MIT, have used the system, which they describe as a “quantum emulator,” to realize the Fermi-Hubbard model of particles interacting within a lattice. [Full article]

Physics in the News icon