Microwave photons emitted by fractionally charged quasiparticles

Abstract

Strongly correlated low-dimensional systems can host exotic elementary excitations carrying a fractional charge $q$ and potentially obeying anyonic statistics. In the fractional quantum Hall effect, their fractional charge has been successfully determined owing to low frequency shot noise measurements. However, a universal method for sensing them unambiguously and unraveling their intricate dynamics was still lacking. Here, we demonstrate that this can be achieved by measuring the microwave photons emitted by such excitations when they are transferred through a potential barrier biased with a dc voltage $V_{\text{dc}}$. We observe that only photons at frequencies $f$ below $q{V}_{\text{dc}}/h$ are emitted. This threshold provides a direct and unambiguous determination of the charge $q$, and a signature of exclusion statistics. Derived initially within the Luttinger model, this feature is also predicted by universal non-equilibrium fluctuation relations which agree fully with our measurements. Our work paves the way for further exploration of anyonic statistics using microwave measurements.

16 pages, 4 figures

References in corpus (6)

• Experimental Test of the High-Frequency Quantum Shot Noise Theory in a Quantum Point Contact
• Relevance of multiple-quasiparticle tunneling between edge states at ν=p/(2np+1)
• Emission and absorption noise in the fractional quantum Hall effect
• High Frequency Dynamics and Third Cumulant of Quantum Noise
• Why a noninteracting model works for shot noise in fractional charge experiments
• A high sensitivity ultra-low temperature RF conductance and noise measurement setup

Cited by in corpus (12)

• Fractional charge and fractional statistics in the quantum Hall effects
• Shot Noise in Mesoscopic Systems: from Single Particles to Quantum Liquids
• Processing quantum signals carried by electrical currents
• Observation of the scaling dimension of fractional quantum Hall anyons
• Observation of edge magnetoplasmon squeezing in a quantum Hall conductor
• Anyon braiding on the single edge of a fractional quantum Hall state
• Quantum transport phenomena induced by time-dependent fields
• Signature of anyonic statistics in the integer quantum Hall regime
• Probing anyon statistics on a single-edge loop in the fractional quantum Hall regime
• Photo-assisted shot noise probes multiple charge carriers in quantum Hall edges
• Testing Kubo formula on a nonlinear quantum conductor driven far from equilibrium via power exchanges
• Colored ${\Delta }_T$ noise probes the topological character of edge modes