Quantum control and long-range quantum correlations in dynamical Casimir arrays

The recent observation of the dynamical Casimir effect in a modulated superconducting waveguide, coronating thirty years of world-wide research, empowered the quantum technology community with a powerful tool to create entangled photons on-chip. In this work we show how, going beyond the single waveguide paradigm using a scalable array, it is possible to create multipartite nonclassical states, with the possibility to control the long-range quantum correlations of the emitted photons. In particular, our finite-temperature theory shows how maximally entangled $NOON$ states can be engineered in a realistic setup. The results here presented open the way to new kinds of quantum fluids of light, arising from modulated vacuum fluctuations in linear systems

Spontaneous Conversion from Virtual to Real Photons in the Ultrastrong Coupling Regime

We show that a spontaneous release of virtual photon pairs can occur in a quantum optical system in the ultrastrong coupling regime. In this regime, which is attracting interest both in semiconductor and superconducting systems, the light-matter coupling rate {\Omega}R becomes comparable to the bare resonance frequency of photons {\omega}0. In contrast to the dynamical Casimir effect and other pair creation mechanisms, this phenomenon does not require external forces or time dependent parameters in the Hamiltonian.Comment: To appear on Phys. Rev. Let

LabVIEW intègre et accélère les processus de développement en physique expérimentale

La physique expérimentale a massivement recours à la programmation d'instruments. Nous présentons deux réalisations LabVIEW du LPSC, pour les expériences GRAAL et PLANCK. En nous appuyant sur ces exemples nous dégagerons certaines qualités qui permetent à LabVIEW d'intégrer l'environnement et les méthodes de la recherche. Enfin nous examinerons des points de concordance profonds entre la technologie LabVIEW et les contraintes techniques de la programmation des expériences

I casi pilota

I paragrafi "Risorse imprenditoriali" ed "Energia grigia" (p. 72-74) sono stati scritti con Nadia Battaglio; "Produzione di energia da fonti rinnovabili" (p. 74-90) con Francesco Stassi; "Ranco Sotto, occasione di sperimentazione" (p. 91-99) con Nadia Battaglio; "Caso studio valle Varaita" (p. 100-105) con Francesco Stassi

High Levels of Exogenous C2-Ceramide Promote Morphological and Biochemical Evidences of Necrotic Features in Thyroid Follicular Cells

CD95 and ceramide are known to be involved in the apoptotic mechanism. The triggering of CD95 induces a cascade of metabolic events that progressively and dramatically modifies the cell shape by intense membrane blebbing, leading to apoptotic bodies production. Although the CD95 pathway has been abundantly described in normal thyrocytes, the effects of cell permeable synthetic ceramide at morphological and biochemical levels are not fully known. In the present study, we show that thyroid follicular cells (TFC) exposed to 20 μM of C2-ceramide for 4 h are characterized by morphological features of necrosis, such as electron-lucent cytoplasm, mitochondrial swelling, and loss of plasma membrane integrity without drastic morphological changes in the nuclei. By contrast, TFC treated with 2 μM of C2-ceramide for 4 h are able to accumulate GD3, activate caspases cascade, and induce apoptosis. Furthermore, we provide evidence that 20 μM of C2-ceramide determine the destruction of mitochondria and are not able to induce PARP cleavage and internucleosomal DNA fragmentation, suggesting that the apoptotic program is not activated during the death process and nuclear DNA is randomly cleaved as the consequence of cellular degeneration. Pretreatment with 30 μM of zVAD-fmk rescued TFC from 2 μM of C2-ceramide-induced apoptosis, whereas, 20 μM of C2-ceramide exposure induced necrotic features. Δψm was obviously altered in cells treated with 20 μM of C2-ceramide for 4 h (75% ± 3.5%) compared with the low percentage (12.5% ± 0.4%) of cells with altered Δψm exposed to 2 μM of C2-ceramide. Whereas, only 20% ± 1.1% of cells treated with anti-CD95 for 1 h showed altered Δψm. Additionally, Bax and Bak, two pro-apoptotic members, seem to be not oligomerized in the mitochondrial membrane following ceramide exposure. These results imply that high levels of exogenous ceramide contribute to the necrotic process in TFC, and may provide key molecular basis to the understanding of thyroid signaling pathways that might promote the apoptotic mechanism in thyroid tumoral cells