Free-electron interactions with photonic GKP states: universal control and quantum error correction

We show that the coherent interaction between free electrons and photons can be used for universal control of continuous-variable photonic quantum states in the form of Gottesman-Kitaev-Preskill (GKP) qubits. Specifically, we find that electron energy combs enable non-destructive measurements of the photonic state and can induce arbitrary gates. Moreover, a single electron interacting with multiple photonic modes can create highly entangled states such as Greenberger-Horne-Zeilinger states and cluster states of GKPs

Observation of the Stimulated Quantum Cherenkov Effect

As charged particles surpass the speed of light in an optical medium they produce radiation - analogously to the way jet planes surpass the speed of sound and produce a sonic boom. This radiation emission, known as the Cherenkov effect, is among the most fundamental processes in electrodynamics. As such, it is used in numerous applications of particle detectors, particle accelerators, light sources, and medical imaging. Surprisingly, all Cherenkov-based applications and experiments thus far were fully described by classical electrodynamics even though theoretical work predicts new Cherenkov phenomena coming from quantum electrodynamics. The quantum description could provide new possibilities for the design of highly controllable light sources and more efficient accelerators and detectors. Here, we provide a direct evidence of the quantum nature of the Cherenkov effect and reveal its intrinsic quantum features. By satisfying the Cherenkov condition for relativistic electron wavefunctions and maintaining it over hundreds of microns, each electron simultaneously accelerates and decelerates by absorbing and emitting hundreds of photons in a coherent manner. We observe this strong interaction in an ultrafast transmission electron microscope, achieving for the first time a phase-matching between a relativistic electron wavefunction and a propagating light wave. Consequently, the quantum wavefunction of each electron evolves into a coherent plateau, analogous to a frequency comb in ultrashort laser pulses, containing hundreds of quantized energy peaks. Our findings prove that the delocalized wave nature of electrons can become dominant in stimulated interactions. In addition to prospects for known applications of the Cherenkov effect, our work provides a platform for utilizing quantum electrodynamics for applications in electron microscopy and in free-electron pump-probe spectroscopy.Comment: 15 pages, 4 figure

Spatiotemporal imaging of 2D polariton wave packet dynamics using free electrons

Peer ReviewedPostprint (author's final draft

Bacterial Effector Binding to Ribosomal Protein S3 Subverts NF-κB Function

Enteric bacterial pathogens cause food borne disease, which constitutes an enormous economic and health burden. Enterohemorrhagic Escherichia coli (EHEC) causes a severe bloody diarrhea following transmission to humans through various means, including contaminated beef and vegetable products, water, or through contact with animals. EHEC also causes a potentially fatal kidney disease (hemolytic uremic syndrome) for which there is no effective treatment or prophylaxis. EHEC and other enteric pathogens (e.g., enteropathogenic E. coli (EPEC), Salmonella, Shigella, Yersinia) utilize a type III secretion system (T3SS) to inject virulence proteins (effectors) into host cells. While it is known that T3SS effectors subvert host cell function to promote diarrheal disease and bacterial transmission, in many cases, the mechanisms by which these effectors bind to host proteins and disrupt the normal function of intestinal epithelial cells have not been completely characterized. In this study, we present evidence that the E. coli O157:H7 nleH1 and nleH2 genes encode T3SS effectors that bind to the human ribosomal protein S3 (RPS3), a subunit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) transcriptional complexes. NleH1 and NleH2 co-localized with RPS3 in the cytoplasm, but not in cell nuclei. The N-terminal region of both NleH1 and NleH2 was required for binding to the N-terminus of RPS3. NleH1 and NleH2 are autophosphorylated Ser/Thr protein kinases, but their binding to RPS3 is independent of kinase activity. NleH1, but not NleH2, reduced the nuclear abundance of RPS3 without altering the p50 or p65 NF-κB subunits or affecting the phosphorylation state or abundance of the inhibitory NF-κB chaperone IκBα NleH1 repressed the transcription of a RPS3/NF-κB-dependent reporter plasmid, but did not inhibit the transcription of RPS3-independent reporters. In contrast, NleH2 stimulated RPS3-dependent transcription, as well as an AP-1-dependent reporter. We identified a region of NleH1 (N40-K45) that is at least partially responsible for the inhibitory activity of NleH1 toward RPS3. Deleting nleH1 from E. coli O157:H7 produced a hypervirulent phenotype in a gnotobiotic piglet model of Shiga toxin-producing E. coli infection. We suggest that NleH may disrupt host innate immune responses by binding to a cofactor of host transcriptional complexes

Conception robuste avec modèles simplifiés de crash (Application au choc lateral d'une automobile)

Dans ce mémoire, une méthode innovante de Conception Robuste est développée, puis appliquée au cas du choc latéral d'une automobile. Elle s'appuie sur le cycle en V de l'Ingénierie Sytème et la construction de modèles physiques justes nécessaires. Ces modèles sont utilisés à chaque niveau du cycle pour réaliser des optimisations robustes à moindre coût avant de décliner les meilleures cibles fonctionnelles au niveau suivant, en termes de Qualité/Coût/Délai. Ce raisonnement fonctionnel par étapes permet de gérer la complexité et de favoriser l'innovation en respectant la progressivité du processus de conception tel qu'il existe aujourd'hui dans les entreprises industrielles. La méthode proposée permet ainsi de maximiser les chances d'aboutir rapidement à un produit qui satisfait au mieux les exigences initiales du Projet. La modélisation simplifiée d'une structure au crash est mise en perpective dans cette démarche de conception. L'analogie entre la construction de modèles simplifiés fonctionnels et le processus de conception est soulignée. Un tel modèle est présenté pour le choc latéral d'une automobile. Une modélisation simplifiée des parties peu déformées d'un modèle éléments finis de crash est également proposée, basée sur l'utilisation d'une synthèse modale élastique en grands déplacements. On réduit ainsi le coût de simulation des modèles de véhicules d'environ vingt pourcents pour une très faible dégradation de la précision des résultats. Cette nouvelle modélisation a été validée sur un cas quasi-industriel de crash automobile. Elle trouve de multiples applications dans la démarche de Conception Robuste proposée.In this PhD thesis, an innovative robuste design process is developed and then applied to the design of a motocar for side impact. It is based on the V-shapped cycle of System Engineering and the construction of simplifieds physical models. These models are used at each level of the cycle to perform low cost robust optimization before specifying the best functional targets ti the next level, in terms of Quality/Cost/Delivery. By respecting the progressiveness of the design process, this step by step functional reasoning helps to manage complexity andd favors innovation. Thus, the proposed method maximizes chance to reach quickly a design that statisfies at best the initial expectations of the Project. Simplified crash modeling is presented within the framework of the proposed design method. The analogy between the construction of simplified models and the design process is undelined. Such a model is presented, concerning the side impact of a motoorcar. A simplified modeling of parts of a crash model experiencing small strains is also proposed, based on an elactic component modes synthesis taking into account large displacements. Thus, the simulation cost of full vehicle crash models is recued by twenty percents with a very small loss of accuracy in the results. This new modeling method was valisated on a case of car crash close to an industrial procblem. It can be applied in many ways to help reaching a robust design.LYON-Ecole Centrale (690812301) / SudocSudocFranceF

Reporting of heterogeneity of treatment effect in cohort studies: a review of the literature

Abstract Background This article corresponds to a literature review and analyze how heterogeneity of treatment (HTE) is reported and addressed in cohort studies and to evaluate the use of the different measures to HTE analysis. Methods prospective cohort studies, in English language, measuring the effect of a treatment (pharmacological, interventional, or other) published among 119 core clinical journals (defined by the National Library of Medicine) in the last 16 years were selected in the following data source: Medline. One reviewer randomly sampled journal articles with 1: 1 stratification by journal type: high impact journals (the New England Journal of Medicine, JAMA, LANCET, Annals of Internal Medicine, BMJ and Plos Medicine) and low impact journal (the remaining journals) to identify 150 eligible studies. Two reviewers independently and in duplicate used standardized piloted forms to screen study reports for eligibility and to extract data. They also used explicit criteria to determine whether a cohort study reported HTE analysis. Logistic regression was used to examine the association of prespecified study characteristics with reporting versus not reporting of heterogeneity of treatment effect. Results One hundred fifty cohort studies were included of which 88 (58%) reported HTE analysis. High impact journals (Odds Ratio: 3.5, 95% CI: 1.78–7.5; P < 0.001), pharmacological studies (Odds Ratio: 0.26, 95% CI: 0.13–0.51; P < 0.001) and studies published after 2014 (Odds Ratio: 0.5, 95% CI: 0.25–0.97; P = 0.004) were associated with more frequent reporting of HTE. 27 (31%) studies which reported HTE used an interaction test. Conclusion More than half cohort studies report some measure of heterogeneity of treatment effect. Prospective cohort studies published in high impact journals, with large sample size, or studying a pharmacological treatment are associated with more frequent HTE reporting. The source of funding was not associated with HTE reporting. There is a need for guidelines on how to perform HTE analyses in cohort studies

Flying Couplers Above Spinning Resonators Generate Irreversible Refraction

Creating optical components that allow light to propagate in only one direction - that is, that allow non-reciprocal propagation or \u27isolation\u27 of light - is important for a range of applications. Non-reciprocal propagation of sound can be achieved simply by using mechanical components that spin 1,2 . Spinning also affects de Broglie waves 3, so a similar idea could be applied in optics. However, the extreme rotation rates that would be required, owing to light travelling much faster than sound, lead to unwanted wobbling. This wobbling makes it difficult to maintain the separation between the spinning devices and the couplers to within tolerance ranges of several nanometres, which is essential for critical coupling 4,5 . Consequently, previous applications of optical 6-17 and optomechanical 10,17-20 isolation have used alternative methods. In hard-drive technology, the magnetic read heads of a hard-disk drive fly aerodynamically above the rapidly rotating disk with nanometre precision, separated by a thin film of air with near-zero drag that acts as a lubrication layer 21 . Inspired by this, here we report the fabrication of photonic couplers (tapered fibres that couple light into the resonators) that similarly fly above spherical resonators with a separation of only a few nanometres. The resonators spin fast enough to split their counter-circulating optical modes, making the fibre coupler transparent from one side while simultaneously opaque from the other - that is, generating irreversible transmission. Our setup provides 99.6 per cent isolation of light in standard telecommunication fibres, of the type used for fibre-based quantum interconnects 22 . Unlike flat geometries, such as between a magnetic head and spinning disk, the saddle-like, convex geometry of the fibre and sphere in our setup makes it relatively easy to bring the two closer together, which could enable surface-science studies at nanometre-scale separations