17 research outputs found
Deterministic Generation of Large Fock States
We present a protocol to deterministically prepare the electromagnetic field
in a large photon number state. The field starts in a coherent state and,
through resonant interaction with one or few two-level systems, it evolves into
a coherently displaced Fock state, without any post-selection. We show the
feasibility of the scheme under realistic parameters. The presented method
opens a door to reach Fock states with and optimal fidelities above
%, blurring the line between macroscopic and quantum states of the field
Spatial rogue waves in photorefractive SBN crystals
We report on the excitation of large-amplitude waves, with a probability of
around 1% of total peaks, on a photorefractive SBN crystal by using a simple
experimental setup at room temperature. We excite the system using a narrow
Gaussian beam and observe different dynamical regimes tailored by the value and
time rate of an applied voltage. We identify two main dynamical regimes: a
caustic one for energy spreading and a speckling one for peak emergence. Our
observations are well described by a two-dimensional Schr\"odinger model with
saturable local nonlinearity.Comment: 4 pages, 4 figure
Microwave probes Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas
We show that microwave spectroscopy of a dense Rydberg gas trapped on a
superconducting atom chip in the dipole blockade regime reveals directly the
dipole-dipole many-body interaction energy spectrum. We use this method to
investigate the expansion of the Rydberg cloud under the effect of repulsive
van der Waals forces and the breakdown of the frozen gas approximation. This
study opens a promising route for quantum simulation of many-body systems and
quantum information transport in chains of strongly interacting Rydberg atoms.Comment: PACS: 03.67.-a, 32.80.Ee, 32.30.-
Conditional cash transfers as social policy in Latin America: An assessment of their contributions and limitations
We find the allowed complex overlaps for N equidistant pure quantum states. The accessible overlaps define a petal-shaped area on the Argand plane. Each point inside the petal represents a set of N linearly independent pure states and each point on its contour represents a set of N linearly dependent pure states. We find the optimal probabilities of success of discriminating unambiguously in which of the N equidistant states the system is. We show that the phase of the involved overlap plays an important role in the probability of success. For a fixed overlap modulus, the success probability is highest for the set of states with an overlap with phase equal to zero. In this case, if the process fails, then the information about the prepared state is lost. For states with a phase different from zero, the information could be obtained with an error-minimizing measurement protocol. " 2011 American Physical Society.",,,,,,"10.1103/PhysRevA.84.014302",,,"http://hdl.handle.net/20.500.12104/40278","http://www.scopus.com/inward/record.url?eid=2-s2.0-79961114156&partnerID=40&md5=e1e07a11c52252e84e07c2d60b3fc978",,,,,,"1",,"Physical Review A - Atomic, Molecular, and Optical Physics",,,,"84",,"Scopu
Conclusive discrimination among N equidistant pure states
We find the allowed complex overlaps for N equidistant pure quantum states. The accessible overlaps define a petal-shaped area on the Argand plane. Each point inside the petal represents a set of N linearly independent pure states and each point on its contour represents a set of N linearly dependent pure states. We find the optimal probabilities of success of discriminating unambiguously in which of the N equidistant states the system is. We show that the phase of the involved overlap plays an important role in the probability of success. For a fixed overlap modulus, the success probability is highest for the set of states with an overlap with phase equal to zero. In this case, if the process fails, then the information about the prepared state is lost. For states with a phase different from zero, the information could be obtained with an error-minimizing measurement protocol. © 2011 American Physical Society
Manipulation of multimode squeezing in a coupled waveguide array
© 2019 American Physical Society. ©2019 American Physical Society.We present a scheme for generating and manipulating three-mode squeezed states with genuine tripartite entanglement by injecting single-mode squeezed light into an array of coupled optical waveguides. We explore the possibility to selectively generate single-mode squeezing or multimode squeezing at the output of an elliptical waveguide array, determined solely by the input light polarization. We study the effect of losses in the waveguide array and show that quantum correlations and squeezing are preserved for realistic parameters. Our results show that arrays of optical waveguides are suitable platforms for generating multimode quantum light, which could lead to novel applications in quantum metrology
Comunicazione pubblica e performance nella sanità digitale. trasparenza e accountability per un empowered patient.
Il processo di riforma e di digitalizzazione della pubblica amministrazione italiana (PA) nell'ultimo decennio prevede l'adozione di sistemi di valutazione e gestione della performance delle organizzazioni sanitarie finalizzati a migliorare trasparenza e accountability istituzionale nei confronti dei cittadini e degli stakeholders. In tali processi una comunicazione efficace riveste un ruolo fondamentale per il raggiungimento degli obiettivi che essi si prefiggono, incidendo sull'empowerment del cittadino-paziente. L'autrice riflette sulla centralità e sulle dimensioni della comunicazione pubblica in questo ambito e sulle modalità con cui le organizzazioni sanitarie italiane comunicano online la propria performance, con cenni a best practices internazionali