Making atoms self-magnify reveals their quantum wave functions

Extremely cold atoms have been pushed to self-magnifiers their quantum states so that they can be imagined in unprecedented details. This could help researchers better understand what quantum particles do in strange materials such as superconductors and superfluous.

It is generally very difficult to imagine the quantum states of atoms – that is to say to map the forms of their wave functions – especially when these atoms are closely wrapped in solid materials and interact with each other. To better understand the quantum behavior of these materials, the researchers turn to extremely cold atoms whose quantum properties can be controlled with lasers and electromagnetic radiation, and which can be assembled in closely packaged networks which imitate the arrangement of atoms in solid materials.

Sandra Brandstetter at Heidelberg University in Germany and her colleagues have now designed a way to enlarge the UltraCold atoms’ wave functions to make them even easier to image.

They started with around 30 lithium atoms at a temperature only a few million dollars above absolute zero, the ultimate cold limit. The researchers used lasers to limit these atoms in a flat plan and to control their quantum states, effectively keeping them in a trap made from light. Then, the team changed the properties of this light, loosening the trap in the right way so that the wave functions of the atoms become larger but do not change shape otherwise – them by magnifying effectively. Brandstetter says that light adjustment in this way was like aligning the enlargement lenses under the microscope.

After this step, the team used atom detection methods well established for image the fine details of the wave functions which were previously impossible to analyze. “If we were to imagine the system without prior magnification, we would see only one blob, completely lacking in the capacity to resolve a structure,” explains Brandstetter.

She and her colleagues used the technique to analyze several atom arrangements. For example, they imagined a pair of atoms that interacted with each other, essentially forming a molecule – but due to magnification, the team could solve each atom individually. The most complex system of the new experience included 12 atoms in interaction, each with different quantum laps, a property that determines the magnetic behavior of materials.

Jonathan Mortock at the University of Durham in the United Kingdom says that if similar magnification techniques have been tested before, the new experience is the first to use the approach to identify the quantum behavior of individual atoms in a table. Such a detail was previously impossible to access.

Now, the team wants to use the technique to analyze what is happening when two quantum particles called farmions go to form a fluid that can circulate with zero viscosity or drive electricity with perfect efficiency. These material states could be useful to build better electronic devices, but to realize that objective researchers will need a much deeper understanding of what makes farms get married, and what happens to their quantum states once the twinning has occurred. With the new technique, the researchers could create a pair of ultraccold farmional atoms, then imagine its enlarged wave function to discover it, explains Brandstetter.