Electrons in two-dimensional (2D) systems placed under strong magnetic fields often behave in unique ways, prompting the emergence of so-called fractional quantum Hall liquids. These are exotic states of matter in which electrons behave collectively and form new quasiparticles carrying only a fraction of an electron’s charge and obeying unusual quantum statistics.

In the 1990s, physicists introduced a theory known as the chiral Luttinger liquid theory, which describes the collective movements of these fractional excitations moving in 1D channels along the boundary of 2D fractional quantum Hall states. Nonetheless, past experimental findings were not always aligned with theoretical predictions.

Researchers at Purdue University recently carried out a study aimed at further testing some of the predictions of chiral Luttinger liquid theory by measuring tunneling between 1D edge modes in a device in which a fractional quantum Hall liquid state emerges. Their paper, published in Nature Physics, offers direct experimental evidence of universal anyon tunneling for the n=1/3 fractional quantum Hall state, confirming theoretical predictions made by X.-G. Wen and collaborators in the early 1990s.