Robust quantum coherence above the Fermi sea

Abstract

In this paper we present an experiment where we measured the quantum coherence of a quasiparticle injected at a well-defined energy above the Fermi sea into the edge states of the integer quantum Hall regime. Electrons are introduced in an electronic Mach-Zehnder interferometer after passing through a quantum dot that plays the role of an energy filter. Measurements show that above a threshold injection energy, the visibility of the quantum interferences is almost independent of the energy. This is true even for high energies, up to 130~$\mu$eV, well above the thermal energy of the measured sample. This result is in strong contradiction with our theoretical predictions, which instead predict a continuous decrease of the interference visibility with increasing energy. This experiment raises serious questions concerning the understanding of excitations in the integer quantum Hall regime.

References in corpus (12)

• An On-Demand Coherent Single Electron Source
• Coherence and Indistinguishability of Single Electrons Emitted by Independent Sources
• Direct measurement of the coherence length of edge states in the Integer Quantum Hall Regime
• Production and detection of entangled electron-hole pairs in a degenerate electron gas
• Dephasing in the electronic Mach-Zehnder interferometer at filling factor 2
• Finite bias visibility of the electronic Mach-Zehnder interferometer
• Decoherence and single electron charging in an electronic Mach-Zehnder interferometer
• Noise dephasing in the edge states of the Integer Quantum Hall regime
• Quantum coherence engineering in the integer quantum Hall regime
• Relaxation of an electron wave packet at the quantum Hall edge at filling factor 2
• Interference and multi-particle effects in a Mach-Zehnder interferometer with single-particle sources
• Solution of a model for the two-channel electronic Mach-Zehnder interferometer

Cited by in corpus (28)

• Electron quantum optics as quantum signal processing
• Decoherence and relaxation of a single electron in a one dimensional conductor
• Relaxation and revival of quasiparticles injected in an interacting quantum Hall liquid
• Taming electronic decoherence in 1D chiral ballistic quantum conductors
• Relaxation of an electron wave packet at the quantum Hall edge at filling factor 2
• Dephasing in Mach-Zehnder interferometer by an Ohmic contact
• Spectroscopic study on hot-electron transport in a quantum Hall edge channel
• Charge equilibration in integer and fractional quantum Hall edge channels in a generalized Hall-bar device
• Levitons in superconducting point contacts
• Trapping and counting ballistic non-equilibrium electrons
• Energy relaxation in hot electron quantum optics via acoustic and optical phonon emission
• Charge and energy fractionalization mechanism in one-dimensional channels
• Probing interactions via non-equilibrium momentum distribution and noise in integer quantum Hall systems at $\nu =2$
• Statistical theory of relaxation of high energy electrons in quantum Hall edge states
• Multi-particle interference in an electronic Mach-Zehnder interferometer
• Current correlations of Cooper-pair tunneling into a quantum Hall system
• Spectral properties of interacting helical channels driven by Lorentzian pulses
• Current cross-correlations in a quantum Hall collider at filling factor two
• Coherence recovery mechanisms in quantum Hall edge states
• Electronic wave-packets in integer quantum Hall edge channels: relaxation and dissipative effects
• Detecting weak coupling in mesoscopic systems with a nonequilibrium Fano resonance
• Decoherence of high-energy electrons in weakly disordered quantum Hall edge states
• Charge-conserving equilibration of quantum Hall edge states
• Quantum transport phenomena induced by time-dependent fields
• Asymmetric arms maximise visibility in hot-electron interferometers
• Floquet-Nambu theory of electron quantum optics with superconductors
• Coherent control in quantum transport: amplification, filtering and switching at finite bias
• Fully Tunable Fano Resonances in Chiral Electronic Transport