Abstract The recent developments of electron quantum optics in quantum Hall edge channels have given us new ways to probe the behavior of electrons in quantum conductors. It has brought new quantities called electronic coherences under the spotlight. In this paper, we explore the relations between electron quantum optics and signal processing through a global review of the various methods for accessing single‐ and two‐electron coherences in electron quantum optics. We interpret electron quantum optics interference experiments as analog signal processing, converting quantum signals into experimentally observable quantities such as current averages and correlations. This point of view also gives us a procedure to obtain quantum information quantities from electron quantum optics coherences. We illustrate these ideas by discussing two‐mode entanglement in electron quantum optics. We also sketch how signal processing ideas may open new perspectives for representing electronic coherences in quantum conductors and understand the properties of the underlying many‐body electronic state.Abstract The recent developments of electron quantum optics in quantum Hall edge channels have given us new ways to probe the behavior of electrons in quantum conductors. It has brought new quantities called electronic coherences under the spotlight. In this paper, we explore the relations between electron quantum optics and signal processing through a global review of the various methods for accessing single‐ and two‐electron coherences in electron quantum optics. We interpret electron quantum optics interference experiments as analog signal processing, converting quantum signals into experimentally observable quantities such as current averages and correlations. This point of view also gives us a procedure to obtain quantum information quantities from electron quantum optics coherences. We illustrate these ideas by discussing two‐mode entanglement in electron quantum optics. We also sketch how signal processing ideas may open new perspectives for representing electronic coherences in quantum conductors and understand the properties of the underlying many‐body electronic state.

arXiv:1610.02086physica status solidi (b)Jan 23, 201769 citations

Quantum coherence in electron beams

A. K. Ghatak, Heinrich Hora, Runwen Wang +1 more

Jan 7, 20130 citations

Quantum optics with electron waves

D. C. Glattli

Jan 1, 20070 citations

Two-electron coherence and its measurement in electron quantum optics

É. Thibierge, Dario Ferraro, Benjamin Roussel +4 more

Engineering and studying few-electron states in ballistic conductors is a key step towards understanding entanglement in quantum electronic systems. In this Rapid Communication, we introduce the intrinsic two-electron coherence of an electronic source in quantum Hall edge channels and relate it to two-electron wave functions and to current noise in a Hanbury Brown--Twiss interferometer. Inspired by the analogy with photon quantum optics, we propose to measure the intrinsic two-electron coherence of a source using low-frequency current correlation measurements at the output of a Franson interferometer. To illustrate this protocol, we discuss how it can distinguish between a time-bin-entangled pure state and a statistical mixture of time-shifted electron pairs.Engineering and studying few-electron states in ballistic conductors is a key step towards understanding entanglement in quantum electronic systems. In this Rapid Communication, we introduce the intrinsic two-electron coherence of an electronic source in quantum Hall edge channels and relate it to two-electron wave functions and to current noise in a Hanbury Brown--Twiss interferometer. Inspired by the analogy with photon quantum optics, we propose to measure the intrinsic two-electron coherence of a source using low-frequency current correlation measurements at the output of a Franson interferometer. To illustrate this protocol, we discuss how it can distinguish between a time-bin-entangled pure state and a statistical mixture of time-shifted electron pairs.

arXiv:1503.07446Physical review. B./Physical review. BFeb 12, 201615 citations

Ultrafast optical control of electron spin coherence in charged GaAs quantum dots

M. V. Gurudev Dutt, Jun Cheng, Yanwen Wu +7 more

Impulsive stimulated Raman excitation with coherent optical fields is used for controlling the electron spin coherence in a charged $\mathrm{GaAs}$ quantum dot ensemble through an intermediate charged exciton (trion) state. The interference between two stimulated Raman two-photon quantum mechanical pathways leading to the spin coherence allows us to control the electron spin coherence on the time scale of the Larmor precession frequency. We also demonstrate, both theoretically and experimentally, that ultrafast manipulation of the spin coherence is possible on the time scale of the optical laser frequency, and analyze the limitations due to the trion and spin decoherence times.Impulsive stimulated Raman excitation with coherent optical fields is used for controlling the electron spin coherence in a charged $\mathrm{GaAs}$ quantum dot ensemble through an intermediate charged exciton (trion) state. The interference between two stimulated Raman two-photon quantum mechanical pathways leading to the spin coherence allows us to control the electron spin coherence on the time scale of the Larmor precession frequency. We also demonstrate, both theoretically and experimentally, that ultrafast manipulation of the spin coherence is possible on the time scale of the optical laser frequency, and analyze the limitations due to the trion and spin decoherence times.

Physical Review BSep 13, 200643 citations

Coherence in quantum optics (A)

Roy J. Glauber

Journal of the Optical Society of America AMay 1, 19789 citations

Impulsive stimulated Raman excitation with coherent optical fields is used for controlling the electron spin coherence in a charged

\mathrm{GaAs}

quantum dot ensemble through an intermediate charged exciton (trion) state. The interference between two stimulated Raman two-photon quantum mechanical pathways leading to the spin coherence allows us to control the electron spin coherence on the time scale of the Larmor precession frequency. We also demonstrate, both theoretically and experimentally, that ultrafast manipulation of the spin coherence is possible on the time scale of the optical laser frequency, and analyze the limitations due to the trion and spin decoherence times.