Restriction of movement of quantum particles to one, two, or three dimensions has resulted in the observation of several striking phenomena. An ideal example is the quantization of the Hall conductance recorded in 2D materials in the presence of a strong magnetic field.
Today, although gases of ultracold atoms offer a robust platform for controlling the dimensionality of quantum systems without difficulty, in such setups, it is difficult to measure conductance properties. A “cold-atomic quantum Hall effect” has not yet been observed.
The new study, reported in Physical Review X, suggests a feasible design to accomplish this target. The study was carried out by G. Salerno and N. Goldman from “Physics of Complex Systems and Statistical Mechanics” research unit of Université libre de Bruxelles.
This approach is based on recent experiments at the Swiss Federal Institute of Technology (ETH) in Zurich, where scientists observed the movement of atoms along a 1D wire. The measurement of the quantum Hall effect requires this setup to be extended to two dimensions and the effects of an external magnetic field to be taken into account.
This has been solved by the scientists by introducing a new kind of conductance measurement, which enables the study of real 2D effects starting from a single 1D wire. The main concept is to extend the 1D channel with an added synthetic dimension, which is developed by just shaking the channel: besides traveling along the wire direction, atoms are steered to higher transverse vibrational states, thereby mimicking movement along a transverse lattice.
The out-of-equilibrium approach proposed in this study increases the potentials contributed by atomic wires and provides a highly efficient probe for topological physics in quantum-engineered matter.