Search results for "ASIM"
showing 10 items of 200 documents
Lamb shift of a uniformly accelerated hydrogen atom in the presence of a conducting plate
2009
We investigate the effects of acceleration on the energy-level shifts of a hydrogen atom interacting with the electromagnetic field and in the presence of an infinite perfectly conducting plate. We consider the contributions of vacuum fluctuations and of the radiation reaction field to the Lamb shift, and we discuss their dependence from the acceleration of the atom. We show that, because of the presence of the boundary, both vacuum field fluctuations and radiation reaction field contributions are affected by atomic acceleration. In particular, the effect of the vacuum field fluctuations on the energy-level shifts is not equivalent to that of a thermal field. We also discuss the dependence …
Causality, non-locality and three-body Casimir–Polder energy between three ground-state atoms
2006
The problem of relativistic causality in the time-dependent three-body Casimir–Polder interaction energy between three atoms, initially in their bare ground-state, is discussed. It is shown that the non-locality of the spatial correlations of the electromagnetic field emitted by the atoms during their dynamical self-dressing may become manifest in the dynamical three-body Casimir–Polder interaction energy between the three atoms.
Effects of a uniform acceleration on atom–field interactions
2014
We review some quantum electrodynamical effects related to the uniform acceleration of atoms in vacuum. After discussing the energy level shifts of a uniformly accelerated atom in vacuum, we investigate the atom-wall Casimir-Polder force for accelerated atoms, and the van der Waals/Casimir-Polder interaction between two accelerated atoms. The possibility of detecting the Unruh effect through these phenomena is also discussed in detail.
van der Waals interactions between excited atoms in generic environments
2015
We consider the the van der Waals force involving excited atoms in general environments, constituted by magnetodielectric bodies. We develop a dynamical approach studying the dynamics of the atoms and the field, mutually coupled. When only one atom is excited, our dynamical theory suggests that for large distances the van der Waals force acting on the ground-state atom is monotonic, while the force acting in the excited atom is spatially oscillating. We show how this latter force can be related to the known oscillating Casimir--Polder force on an excited atom near a (ground-state) body. Our force also reveals a population-induced dynamics: for times much larger that the atomic lifetime the …
Theoretical absorption spectrum of the Ar–CO van der Waals complex
2003
The three-dimensional intermolecular electric dipole moment surface of Ar–CO is calculated at the coupled cluster singles and doubles level of theory with the aug-cc-pVTZ basis set extended with a 3s3p2d1f1g set of midbond functions. Using the rovibrational energies and wave functions of our recent study [J. Chem. Phys. 117, 6562 (2002)], temperature-dependent spectral intensities are evaluated and compared to available experimental data. Based on the theoretical spectrum, alternative assignments of the experimentally observed lines in the fundamental band of CO around 2160 and 2166 cm−1 are suggested. Thomas.Bondo@uv.es
Optomechanical Rydberg-atom excitation via dynamic Casimir-Polder coupling
2014
We study the optomechanical coupling of a oscillating effective mirror with a Rydberg atomic gas, mediated by the dynamical atom-mirror Casimir-Polder force. This coupling may produce a near-field resonant atomic excitation whose probability scales as $\propto (d^2\;a\;n^4\;t)^2/z_0^8$, where $z_0$ is the average atom-surface distance, $d$ the atomic dipole moment, $a$ the mirror's effective oscillation amplitude, $n$ the initial principal quantum number, and $t$ the time. We propose an experimental configuration to realize this system with a cold atom gas trapped at a distance $\sim 2\cdot10 \, \mu$m from a semiconductor substrate, whose dielectric constant is periodically driven by an ext…
Integración: una cuestión de derechos
2010
This article achieves a comparative analysis between the Citizenship and Integration Programme (2007-2010) and the spanish Migration Bill Project. Firstly, it aims to analyze whether the concept of integration, as it was introduced as a general principle within the Migration Bill, is consistent with the concept of the Programme. Secondly, it is about to examine how the notion of integration affects some of the provisions, which are introduced by the law reform, especially on fundamental rights. Finally, this leads to assess the implications and strains between migration control policies and integration policies about migrants’.
Krāsu kombināciju un formu simetriju afektīvās reakcijas saskarņu vidē
2020
Cilvēki izmanto saskarnes katru dienu, vairākas reizes dienā, ir svarīgi domāt ne tikai par saskarnes funkcionalitāti, bet arī par tās emocionālu pienesumu. Divi svarīgi aspekti, kas spēj ietekmēt lietotāju afektīvās reakcijas ir : saskarnē izmantotās formas un krāsu kombinācijas. Darba teorētiskajā daļā tiek apskatīta formu un krāsu kombināciju emocionālā ietekme : (1) Vai lietotāji pozitīvāk reaģēs uz simetriskām vai asimetriskām formām; (2) kādām krāsu shēmām lietotāji dos priekšroku; (3) kā afektīvās reakcijas atšķiras dažādu lietotāju vidū. Praktiskajā daļā tiek pētīts kādas, emocijas dažādām lietotāju grupām, izraisa saskarnes, kurās izmantotas simetriskas vai asimetriskas formas un h…
Romanzo giallo e aporia della verità: Spasimo di Federico De Roberto
2010
Il saggio analizza la struttura del giallo e i suoi rovesciamenti in Spasimo di Federico De Roberto.
Dynamical Casimir-Polder forces
2011
We consider the dynamical Casimir-Polder force on an atom placed near an infinite conducting wall. The system is initially in a non equilibrium configuration such as a bare or a partially dressed state, and its time evolution is considered as well as the time dependence of the atom-wall Casimir-Polder interaction. A possible scheme to generate experimentally the initial partially dressed state and to detect the dynamical Casimir-Polder force is discussed.