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Trento, Italy

The University of Trento is an Italian university located in Trento and nearby Rovereto. It has been able to achieve considerable results in didactics, research, and international relations according to CENSIS and the Italian Ministry of Education.The didactic and scientific activities are concentrated around three main “areas”: the city area, with the Faculties of Economics, Sociology, Law, Arts and Humanities; the hill area, with the Faculties of Mathematical, Physical and Life science and the Faculty of Engineering; and the Faculty of Cognitive science at Rovereto. Wikipedia.

Carusotto I.,University of Trento | Ciuti C.,University Paris Diderot
Reviews of Modern Physics | Year: 2013

This article reviews recent theoretical and experimental advances in the fundamental understanding and active control of quantum fluids of light in nonlinear optical systems. In the presence of effective photon-photon interactions induced by the optical nonlinearity of the medium, a many-photon system can behave collectively as a quantum fluid with a number of novel features stemming from its intrinsically nonequilibrium nature. A rich variety of recently observed photon hydrodynamical effects is presented, from the superfluid flow around a defect at low speeds, to the appearance of a Mach-Cherenkov cone in a supersonic flow, to the hydrodynamic formation of topological excitations such as quantized vortices and dark solitons at the surface of large impenetrable obstacles. While the review is mostly focused on a specific class of semiconductor systems that have been extensively studied in recent years (planar semiconductor microcavities in the strong light-matter coupling regime having cavity polaritons as elementary excitations), the very concept of quantum fluids of light applies to a broad spectrum of systems, ranging from bulk nonlinear crystals, to atomic clouds embedded in optical fibers and cavities, to photonic crystal cavities, to superconducting quantum circuits based on Josephson junctions. The conclusive part of the article is devoted to a review of the future perspectives in the direction of strongly correlated photon gases and of artificial gauge fields for photons. In particular, several mechanisms to obtain efficient photon blockade are presented, together with their application to the generation of novel quantum phases. © 2013 American Physical Society. Source

Dumbser M.,University of Trento
Computer Methods in Applied Mechanics and Engineering | Year: 2013

In this article the weakly compressible two-phase diffuse interface method (DIM) for the simulation of complex two-dimensional non-hydrostatic free surface flows proposed by Dumbser in [24] is extended to three-dimensional unstructured tetrahedral meshes. As in the 2D case, a reduced version of the Baer-Nunziato model for compressible multiphase flows is used. The physical model is closed by the Tait equation of state for water and can be implemented easily into existing compressible codes based on high resolution shock capturing finite volume schemes. Since the proposed model is fully three-dimensional, it includes the fluid accelerations in gravity direction and hence does not assume a hydrostatic pressure distribution, like the classical shallow water equations. Furthermore, the 3D two-phase model can naturally deal also with breaking waves. To solve the system of conservation laws of mass and momentum coupled with the non-conservative evolution equation of the fluid volume fraction, a high order path-conservative one-step WENO finite volume scheme is applied, together with a new generalized Osher-type Riemann solver at the element interfaces. The accurate Riemann solver in combination with a high order finite volume approach leads to a simple but sharp resolution of the free surface.A thorough comparison of experimental reference data with the computational results obtained for a large set of three-dimensional test cases shows the suitability of the present approach for the accurate simulation of complex three-dimensional free surface flows. The use of a compressible flow model allows the method to simulate both, low speed and high speed free surface flow problems, which makes the approach applicable to a very wide class of environmental and industrial free surface flow problems. © 2013 Elsevier B.V. Source

Lutterotti L.,University of Trento
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2010

A global approach has been developed to analyze complex thin film structures by X-ray diffraction. The method is based on the fitting of multiple data, diffraction pattern and/or images, collected at different orientation of the sample to obtain all the information needed. It requires the knowledge of the crystal structure for the phases present in the film, or if the amount/film thickness is sufficient, the crystal structure can be also determined or refined. Reflectivity patterns can be added to the global refinement to improve the accuracy of the thickness determination and when coupled with total X-ray fluorescence can give the in depth chemical concentrations. In addition, it constraints the solution for the quantitative phase analysis obtained from the diffraction patterns. The principles of the analysis with the main methods will be presented from the theoretical point of view. These cover the models from crystal structure to texture, residual strain/stresses, crystallite sizes and microstrains. To make the method more effective, some specific models have been developed in the past few years. Then some experimental/analysis examples will be given to enlighten how the method works and what kind of information can be obtained. Not every model suits every analysis or kind of thin film and the examples will cover different cases from multiple phases to strong texture, epitaxial thin films or multilayers. © 2009 Elsevier B.V. All rights reserved. Source

Peelen M.V.,University of Trento | Kastner S.,Princeton University
Trends in Cognitive Sciences | Year: 2014

The efficient selection of behaviorally relevant objects from cluttered environments supports our everyday goals. Attentional selection has typically been studied in search tasks involving artificial and simplified displays. Although these studies have revealed important basic principles of attention, they do not explain how the brain efficiently selects familiar objects in complex and meaningful real-world scenes. Findings from recent neuroimaging studies indicate that real-world search is mediated by 'what' and 'where' attentional templates that are implemented in high-level visual cortex. These templates represent target-diagnostic properties and likely target locations, respectively, and are shaped by object familiarity, scene context, and memory. We propose a framework for real-world search that incorporates these recent findings and specifies directions for future study. © 2014 Elsevier Ltd. Source

Reeder R.R.,University of Trento
Journal of vision | Year: 2013

Visual search involves the matching of visual input to a "search template," an internal representation of task-relevant information. The present study investigated the contents of the search template during visual search for object categories in natural scenes, for which low-level features do not reliably distinguish targets from nontargets. Subjects were cued to detect people or cars in diverse photographs of real-world scenes. On a subset of trials, the cue was followed by task-irrelevant stimuli instead of scenes, directly followed by a dot that subjects were instructed to detect. We hypothesized that stimuli that matched the active search template would capture attention, resulting in faster detection of the dot when presented at the location of a template-matching stimulus. Results revealed that silhouettes of cars and people captured attention irrespective of their orientation (0°, 90°, or 180°). Interestingly, strong capture was observed for silhouettes of category-diagnostic object parts, such as the wheel of a car. Finally, attentional capture was also observed for silhouettes presented at locations that were irrelevant to the search task. Together, these results indicate that search for familiar object categories in real-world scenes is mediated by spatially global search templates that consist of view-invariant shape representations of category-diagnostic object parts. Source

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