Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2602.23973 · Low Temperature Physics

Effect of electron-electron interactions on the propagation of ultrashort voltage pulses in a Mach-Zehnder interferometer

Prasoon Kumar, Thomas Kloss, Xavier Waintal

cond-mat.mes-hallcond-mat.str-elquant-phSubmitted Feb 27, 2026• Announced Mar 2, 2026• 0 citations
arXivHTMLPDF

Abstract

Electronic interferometers have been identified as possible candidates for building electronic flying qubits. Such a regime requires ultrafast voltage pulses whose duration is shorter than the time of flight through the device. Understanding the corresponding physics in the presence of such short excitations requires a proper treatment of electron-electron interactions. In this article, we take a step in this direction by performing time-resolved simulations of a Mach-Zehnder interferometer treating the interactions at the time-dependent mean-field level. We find that the main effect of the interaction is the renormalization of the pulse velocity. Very importantly, the interference effects appear to be robust to the presence of interactions.

Journal reference
Low Temp. Phys. 52, 1036-1047 (2026)
DOI
10.1063/10.0044811

Related papers

Multi-Particle Interference in an Electronic Mach–Zehnder Interferometer

Janne Kotilahti, Pablo Burset, Michael Moskalets +1 more

The development of dynamic single-electron sources has made it possible to observe and manipulate the quantum properties of individual charge carriers in mesoscopic circuits. Here, we investigate multi-particle effects in an electronic Mach-Zehnder interferometer driven by a series of voltage pulses. To this end, we employ a Floquet scattering formalism to evaluate the interference current and the visibility in the outputs of the interferometer. An injected multi-particle state can be described by its first-order correlation function, which we decompose into a sum of elementary correlation functions that each represent a single particle. Each particle in the pulse contributes independently to the interference current, while the visibility (given by the maximal interference current) exhibits a Fraunhofer-like diffraction pattern caused by the multi-particle interference between different particles in the pulse. For a sequence of multi-particle pulses, the visibility resembles the diffraction pattern from a grid, with the role of the grid and the spacing between the slits being played by the pulses and the time delay between them. Our findings may be observed in future experiments by injecting multi-particle pulses into a Mach-Zehnder interferometer.

arXiv:2104.13136•Entropy•Jun 10, 2021•13 citations

Electronic interferometry with ultrashort plasmonic pulses

Seddik Ouacel, Lucas Mazzella, Thomas Kloss +17 more

Electronic flying qubits offer an interesting alternative to photonic qubits: electrons propagate slower, hence easier to control in real time, and Coulomb interaction enables direct entanglement between different qubits. Although their coherence time is limited, flying electrons in the form of picosecond plasmonic pulses could be competitive in terms of the number of achievable coherent operations. The key challenge in achieving this critical milestone is the development of a new technology capable of injecting ‘on-demand’ single-electron wavepackets into quantum devices, with temporal durations comparable to or shorter than the device dimensions. Here, we take a significant step towards achieving this regime in a quantum nanoelectronic system by injecting ultrashort single-electron plasmonic pulses into a 14-micrometer-long Mach-Zehnder interferometer. Our results establish that quantum coherence is robust under the on-demand injection of ultrashort plasmonic pulses, as evidenced by the observation of coherent oscillations in the single-electron regime. Building on this, our results demonstrate the existence of a “non-adiabatic" regime that is prominent at high frequencies. This result highlights the potential of flying qubits as a promising alternative to localised qubit architectures, offering advantages such as a reduced hardware footprint, enhanced connectivity, and scalability for quantum information processing. The development of electronic flying qubits requires the ability to generate and control single-electron excitations. Here the authors demonstrate quantum coherence of ultrashort single-electron plasmonic pulses in an electronic Mach-Zehnder interferometer, revealing a non-adiabatic regime at high frequencies.

arXiv:2408.13025•Nature Communications•May 19, 2025•9 citations

Quantum Sensing of Time-Dependent Electromagnetic Fields with Single-Electron Excitations

Hubert Souquet-Basiège, Benjamin Roussel, Giacomo Rebora +4 more

In this study, we investigate the potential of electronic interferometers for probing the quantum state of electromagnetic radiation on a chip at subnanosecond timescales. We propose to use single-electron excitations propagating within an electronic Mach-Zehnder interferometer in the Aharonov-Bohm-dominated regime. We discuss how information about the quantum state of the electromagnetic radiation is encoded into the interference contribution to the average outgoing electrical current. By investigating squeezed radiation and single-edge magnetoplasmons probed by leviton pulses in a realistic setup, we show that single-electron interferometers have the potential to probe quantum radiation in the time domain with subnanosecond to picosecond time resolution. Our research could have significant implications for probing the fundamental properties of light in the microwave to terahertz domains at extremely short timescales.

arXiv:2405.05796•Physical Review X•Jun 3, 2025•4 citations

Dephasing by electron-electron interactions in a ballistic Mach-Zehnder interferometer

Neuenhahn, C., Marquardt, F.

We consider a ballistic Mach-Zehnder interferometer for electrons propagating chirally in one dimension (such as in an integer quantum Hall effect edge channel). In such a system, dephasing occurs when the finite range of the interaction potential is taken into account. Using the tools of bosonization, we discuss the decay of coherence as a function of propagation distance and energy. We supplement the exact solution by a semiclassical approach that is physically transparent and is exact at high energies. In particular, we study in more detail the recently predicted universal power-law decay of the coherence at high energies, where the exponent does not depend on the interaction strength. In addition, we compare against Keldysh perturbation theory, which works well for small interaction strength at short propagation distances.

•Nov 20, 2008•8 citations

Dephasing by electron–electron interactions in a ballistic Mach–Zehnder interferometer

Clemens Neuenhahn, Florian Marquardt

We consider a ballistic Mach–Zehnder interferometer for electrons propagating chirally in one dimension (such as in an integer quantum Hall effect edge channel). In such a system, dephasing occurs when the finite range of the interaction potential is taken into account. Using the tools of bosonization, we discuss the decay of coherence as a function of propagation distance and energy. We supplement the exact solution by a semiclassical approach that is physically transparent and is exact at high energies. In particular, we study in more detail the recently predicted universal power-law decay of the coherence at high energies, where the exponent does not depend on the interaction strength. In addition, we compare against Keldysh perturbation theory, which works well for small interaction strength at short propagation distances.

arXiv:0903.2036•New Journal of Physics•Nov 20, 2008•21 citations

Electron collision in a two-path graphene interferometer

Himadri Chakraborti, L. Pugliese, Alexandre Assouline +7 more

The collision of two electrons at a beam splitter provides a method for studying their coherence and indistinguishability. Its realization requires the on-demand generation and synchronization of single electrons. In this work, we demonstrate the coherent collision of single electrons, generated by voltage pulses, in a graphene Mach-Zehnder interferometer. By measuring shot noise resulting from the collisions, we unveil fundamental characteristics of colliding electrons, highlighting the complementarity between the indistinguishable and distinguishable parts of their wave functions. The former is manifested through fermionic Hong-Ou-Mandel destructive interference, whereas the latter is discerned through double-winding Aharonov-Bohm interference in the noise. The interference visibilities of around 60% enable comprehensive quantum state tomography. Our findings may place coherent operations involving flying qubits within reach in graphene.

Science•May 1, 2025•8 citations
Electronic interferometers have been identified as possible candidates for building electronic flying qubits. Such a regime requires ultrafast voltage pulses whose duration is shorter than the time of flight through the device. Understanding the corresponding physics in the presence of such short excitations requires a proper treatment of electron-electron interactions. In this article, we take a step in this direction by performing time-resolved simulations of a Mach-Zehnder interferometer treating the interactions at the time-dependent mean-field level. We find that the main effect of the interaction is the renormalization of the pulse velocity. Very importantly, the interference effects appear to be robust to the presence of interactions.
The development of dynamic single-electron sources has made it possible to observe and manipulate the quantum properties of individual charge carriers in mesoscopic circuits. Here, we investigate multi-particle effects in an electronic Mach-Zehnder interferometer driven by a series of voltage pulses. To this end, we employ a Floquet scattering formalism to evaluate the interference current and the visibility in the outputs of the interferometer. An injected multi-particle state can be described by its first-order correlation function, which we decompose into a sum of elementary correlation functions that each represent a single particle. Each particle in the pulse contributes independently to the interference current, while the visibility (given by the maximal interference current) exhibits a Fraunhofer-like diffraction pattern caused by the multi-particle interference between different particles in the pulse. For a sequence of multi-particle pulses, the visibility resembles the diffraction pattern from a grid, with the role of the grid and the spacing between the slits being played by the pulses and the time delay between them. Our findings may be observed in future experiments by injecting multi-particle pulses into a Mach-Zehnder interferometer.
Electronic flying qubits offer an interesting alternative to photonic qubits: electrons propagate slower, hence easier to control in real time, and Coulomb interaction enables direct entanglement between different qubits. Although their coherence time is limited, flying electrons in the form of picosecond plasmonic pulses could be competitive in terms of the number of achievable coherent operations. The key challenge in achieving this critical milestone is the development of a new technology capable of injecting ‘on-demand’ single-electron wavepackets into quantum devices, with temporal durations comparable to or shorter than the device dimensions. Here, we take a significant step towards achieving this regime in a quantum nanoelectronic system by injecting ultrashort single-electron plasmonic pulses into a 14-micrometer-long Mach-Zehnder interferometer. Our results establish that quantum coherence is robust under the on-demand injection of ultrashort plasmonic pulses, as evidenced by the observation of coherent oscillations in the single-electron regime. Building on this, our results demonstrate the existence of a “non-adiabatic" regime that is prominent at high frequencies. This result highlights the potential of flying qubits as a promising alternative to localised qubit architectures, offering advantages such as a reduced hardware footprint, enhanced connectivity, and scalability for quantum information processing. The development of electronic flying qubits requires the ability to generate and control single-electron excitations. Here the authors demonstrate quantum coherence of ultrashort single-electron plasmonic pulses in an electronic Mach-Zehnder interferometer, revealing a non-adiabatic regime at high frequencies.
In this study, we investigate the potential of electronic interferometers for probing the quantum state of electromagnetic radiation on a chip at subnanosecond timescales. We propose to use single-electron excitations propagating within an electronic Mach-Zehnder interferometer in the Aharonov-Bohm-dominated regime. We discuss how information about the quantum state of the electromagnetic radiation is encoded into the interference contribution to the average outgoing electrical current. By investigating squeezed radiation and single-edge magnetoplasmons probed by leviton pulses in a realistic setup, we show that single-electron interferometers have the potential to probe quantum radiation in the time domain with subnanosecond to picosecond time resolution. Our research could have significant implications for probing the fundamental properties of light in the microwave to terahertz domains at extremely short timescales.
We consider a ballistic Mach-Zehnder interferometer for electrons propagating chirally in one dimension (such as in an integer quantum Hall effect edge channel). In such a system, dephasing occurs when the finite range of the interaction potential is taken into account. Using the tools of bosonization, we discuss the decay of coherence as a function of propagation distance and energy. We supplement the exact solution by a semiclassical approach that is physically transparent and is exact at high energies. In particular, we study in more detail the recently predicted universal power-law decay of the coherence at high energies, where the exponent does not depend on the interaction strength. In addition, we compare against Keldysh perturbation theory, which works well for small interaction strength at short propagation distances.
We consider a ballistic Mach–Zehnder interferometer for electrons propagating chirally in one dimension (such as in an integer quantum Hall effect edge channel). In such a system, dephasing occurs when the finite range of the interaction potential is taken into account. Using the tools of bosonization, we discuss the decay of coherence as a function of propagation distance and energy. We supplement the exact solution by a semiclassical approach that is physically transparent and is exact at high energies. In particular, we study in more detail the recently predicted universal power-law decay of the coherence at high energies, where the exponent does not depend on the interaction strength. In addition, we compare against Keldysh perturbation theory, which works well for small interaction strength at short propagation distances.
The collision of two electrons at a beam splitter provides a method for studying their coherence and indistinguishability. Its realization requires the on-demand generation and synchronization of single electrons. In this work, we demonstrate the coherent collision of single electrons, generated by voltage pulses, in a graphene Mach-Zehnder interferometer. By measuring shot noise resulting from the collisions, we unveil fundamental characteristics of colliding electrons, highlighting the complementarity between the indistinguishable and distinguishable parts of their wave functions. The former is manifested through fermionic Hong-Ou-Mandel destructive interference, whereas the latter is discerned through double-winding Aharonov-Bohm interference in the noise. The interference visibilities of around 60% enable comprehensive quantum state tomography. Our findings may place coherent operations involving flying qubits within reach in graphene.