Anyons in Quantum Circuits – ANYQUAC

Central to Quantum Mechanics is the division of particles between bosons and fermions. Nevertheless, this distinction has been
theoretically challenged from the 80s on. In reduced dimensionality, particles coined “anyons” can exist, with a fractional exchange
phase intermediate between bosons and fermions. Early on, theoreticians identified quasiparticles of the Fractional Quantum Hall
(FQH) regime as anyon candidates, and their fractional statistics was recently established in two pioneer experiments. However, the
stringent experimental conditions under which these anyonic states naturally emerge make their study extremely challenging and
hinders any fast progress in their understanding and manipulation.
In the ANYQUAC project, I will implement a novel approach by constructing anyons in the Integer Quantum Hall (IQH) regime with
quantum circuit tools, following recent theoretical proposals. While the FQH regime and its fractional excitations emerge from hardly
controlled microscopic Coulomb interactions, here, fractionalization arises from the charging energy of mesoscopic islands
correlating charge transport in edge channels of the IQH regime. The latter offers many advantages compared to its fractional
counterpart: its basic physics is non-interacting and its conductance plateaus are metrologically robust over far more relaxed
experimental conditions. The interaction strength will be directly provided by the tunable IQH filling factor and charging energy,
enabling fractionalizations that are unreachable in the FQH regime. Combining ultrasensitive conductance and current shot noise
measurements, electronic Mach-Zehnder interferometry and high frequency techniques, I will reveal the anyonic nature of the
system’s excitations and characterize their quantum coherence, highlight their similarities and differences from their FQH cousins.
This will be a major leap in the emergence of anyon quantum optics with strongly correlated tunable model systems.