We consider an electronic Hong-Ou-Mandel interferometer in the integer quantum Hall regime, where the colliding electronic states are generated by applying voltage pulses (creating for instance Levitons) to ohmic contacts. The aim of this work is to investigate possible mechanisms leading to a reduced visibility of the Pauli dip, i.e., the noise suppression expected for synchronized sources. It is known that electron-electron interactions cannot account for this effect and always lead to a full suppression of the Hong-Ou-Mandel noise. Focusing on the case of filling factor $ν=2$, we show instead that a reduced visibility of the Pauli dip can result from mixing of the copropagating edge channels, arising from tunneling events between them.
We investigate heat current fluctuations induced by a periodic train of Lorentzian-shaped pulses, carrying an integer number of electronic charges, in a Hong-Ou-Mandel interferometer implemented in a quantum Hall bar in the Laughlin sequence. We demonstrate that the noise in this collisional experiment cannot be reproduced in a setup with a single drive, in contrast to what is observed in the charge noise case. Nevertheless, the simultaneous collision of two identical levitons always leads to a total suppression even for the Hong-Ou-Mandel heat noise at all filling factors, despite the presenc…
We review and develop recent results regarding Leviton excitations generated in topological states of matter - such as integer and fractional quantum Hall edge channels - and carrying a charge multiple of the electronic one. The peculiar features associated to these clean and robust emerging excitations can be detected through current correlation measurements. In particular, relevant information can be extracted from the noise signal in generalized Hong-Ou-Mandel experiments, where Levitons with different charges collide against each other at a quantum point contact. We describe this quantity …
Coulomb interaction has a striking effect on electronic propagation in one dimensional conductors. The interaction of an elementary excitation with neighboring conductors favors the emergence of collective modes which eventually leads to the destruction of the Landau quasiparticle. In this process, an injected electron tends to fractionalize into separated pulses carrying a fraction of the electron charge. Here we use two-particle interferences in the electronic analog of the Hong-Ou-Mandel experiment in a quantum Hall conductor at filling factor 2 to probe the fate of a single electron emitte…
Electronic Hong-Ou-Mandel interferometer for multi-mode entanglement detection
我们证明了在Hong-Ou-Mandel干涉仪中通过测量零频率电流关联可以检测到介观导体中电子的多模纠缠。通过这种方法,可以进一步建立两电子输入态形成纠缠的下界。我们的结果扩展了Burkard和Loss的工作[Phys. Rev. Lett. 91,087903(2003)],并提供了一种方法来测试涉及轨道和自旋自由度的纠缠态的存在。
We consider a device which allows to create and probe single Majorana fermions, in the form of Bogoliubov quasiparticles. It is composed of two counter-propagating edge channels, each put in proximity with a superconducting region where Andreev reflection operates, and which thus converts electrons into Bogoliubov quasiparticles. The edge channels then meet at a quantum point contact where collisions can be achieved. A voltage biased version of the setup was studied in Phys. Rev. Lett. 112, 070604 (2014) and showed non-local interference phenomena and signatures of Bogoliubov quasiparticle col…
The electronic Hong-Ou-Mandel interferometer in the integer quantum Hall regime is an ideal system to probe the building up of quantum correlations between charge carriers and it has been proposed as a viable platform for quantum computing gates. Using a parallel implementation of the split-step Fourier method, we simulated the antibunching of two interacting fermionic wave packets impinging on a quantum point contact. Numerical results of the exact approach are compared with a simplified theoretical model based on one-dimensional scattering formalism. We show that, for a realistic geometry, t…
The interplay between single-particle interference and quantum indistinguishability leads to signature correlations in many-body scattering. We uncover these with a semiclassical calculation of the transmission probabilities through mesoscopic cavities for systems of non-interacting particles. For chaotic cavities we provide the universal form of the first two moments of the transmission probabilities over ensembles of random unitary matrices, including weak localization and dephasing effects. If the incoming many-body state consists of two macroscopically occupied wavepackets, their time dela…
We probe the indistinguishability of photons emitted by a semiconductor quantum dot (QD) via time- and temperature- dependent two-photon interference (TPI) experiments. An increase in temporal-separation between consecutive photon emission events, reveals a decrease in TPI visibility on a nanosecond timescale, theoretically described by a non-Markovian noise process in agreement with fluctuating charge-traps in the QD's vicinity. Phonon-induced pure dephasing results in a decrease in TPI visibility from $(96\pm4)\,$\% at 10\,K to a vanishing visibility at 40\,K. In contrast to Michelson-type m…
Scalable quantum photonic technologies require low-loss integration of many identical single-photon sources with photonic circuitry on a chip. Relatively complex quantum photonic circuits have already been demonstrated; however, sources used so far relied on parametric-down-conversion. Hence, the efficiency and scalability are intrinsically limited by the probabilistic nature of the sources. Quantum emitter-based single-photon sources are free of this limitation, but frequency matching of multiple emitters within a single circuit remains a challenge. In this work, we demonstrate a key componen…