Anyons in quantum Hall interferometry

The quantum Hall (QH) effect represents a unique playground where quantum coherence of electrons can be exploited for various applications, from metrology to quantum computation. In the fractional regime, it also hosts anyons, emergent quasiparticles that are neither bosons nor fermions and possess fractional statistics. Their detection and manipulation represent key milestones in view of topologically protected quantum computation schemes. Exploiting the high degree of phase coherence, edge states in the QH regime have been investigated by designing and constructing electronic interferometers, able to reveal the coherence and statistical properties of the interfering constituents. Here, we review the two main geometries developed in the QH regime, the Mach–Zehnder and the Fabry–Perot interferometers. We present their basic working principles, fabrication methods and the main results obtained in both the integer and the fractional QH regimes. We will also show how recent technological advances led to the direct experimental demonstration of fractional statistics for Laughlin quasiparticles in a Fabry–Perot interferometric setup. Quantum Hall systems represent an example of topological quantum matter, where quasiparticles with fractional statistics (anyons) may emerge. This Technical Review presents a survey of recent developments in quantum Hall interferometry.