Search results for " ATO"
showing 10 items of 1592 documents
Measurement of ultra-low heating rates of a single antiproton in a cryogenic Penning trap
2019
Physical review letters 122(4), 043201 (2019). doi:10.1103/PhysRevLett.122.043201
Electroluminescence TPCs at the thermal diffusion limit
2019
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM
Multicenter solutions in Eddington-inspired Born-Infeld gravity
2020
We find multicenter (Majumdar-Papapetrou type) solutions of Eddington-inspired Born-Infeld gravity coupled to electromagnetic fields governed by a Born-Infeld-like Lagrangian. We construct the general solution for an arbitrary number of centers in equilibrium and then discuss the properties of their one-particle configurations, including the existence of bounces and the regularity (geodesic completeness) of these spacetimes. Our method can be used to construct multicenter solutions in other theories of gravity.
Coherent axion-photon transformations in the forward scattering on atoms
2018
In certain laboratory experiments the production and/or detection of axions is due to the photon-axion transformations in a strong magnetic field. This process is coherent, and the rate of the transformation is proportional to the length $l$ and magnitude $B$ of the magnetic field squared, $\sim l^2B^2$. In the present paper, we consider coherent production of axions due to the forward scattering of photons on atoms or molecules. This process may be represented as being due to an effective electromagnetic field which converts photons to axions. We present analytical expressions for such effective magnetic and electric fields induced by resonant atomic M0 and M1 transitions, as well as give …
Energy level shifts of a uniformly accelerated atom in the presence of boundary conditions
2009
We discuss the radiative level shifts of an atom moving with uniform acceleration near an infinite reflecting plate. We first consider the case of a two-level system interacting with a massless scalar field in the vacuum state. The acceleration of the two-level atom is supposed in a direction parallel to the conducting plate. We evaluate the contribution of vacuum fluctuations and of the radiation reaction field to the energy shift of the atomic levels, and discuss their behaviour as a function of the atomic acceleration and of the atom-plate distance. Then, we investigate the more general case of an hydrogen atom accelerating near a perfectly reflecting plate and interacting with the elect…
First operation of the superconducting Darmstadt linear electron accelerator as an energy recovery linac
2020
The superconducting Darmstadt linear electron accelerator (S-DALINAC) has been operated as an energy recovery linac (ERL) for the first time. The S-DALINAC is a recirculating superconducting radio-frequency (SRF) accelerator and had been upgraded with an additional recirculation beamline. It features a path length adjustment system that provides a freedom of choice of 360\ifmmode^\circ\else\textdegree\fi{} for the rf phase difference between the electron bunches recirculated through the new beamline and the phase of the accelerating ${\mathrm{TM}}_{010}$ mode of the oscillating electromagnetic field in the SRF cavities of the accelerator. A choice of around 180\ifmmode^\circ\else\textdegree…
A weakly-interacting many-body system of Rydberg polaritons based on electromagnetically induced transparency
2020
We proposed utilizing a medium with a high optical depth (OD) and a Rydberg state of low principal quantum number, $n$, to create a weakly-interacting many-body system of Rydberg polaritons, based on the effect of electromagnetically induced transparency (EIT). We experimentally verified the mean field approach to weakly-interacting Rydberg polaritons, and observed the phase shift and attenuation induced by the dipole-dipole interaction (DDI). The DDI-induced phase shift or attenuation can be viewed as a consequence of the elastic or inelastic collisions among the Rydberg polaritons. Using a weakly-interacting system, we further observed that a larger DDI strength caused a width of the mome…
Comparative density-functional LCAO and plane-wave calculations ofLaMnO3surfaces
2005
We compare two approaches to the atomic, electronic, and magnetic structures of LaMnO3 bulk and the (001), (110) surfaces—hybrid B3PW with optimized LCAO basis set (CRYSTAL-2003 code) and GGA-PW91 with plane-wave basis set (VASP 4.6 code). Combining our calculations with those available in the literature, we demonstrate that combination of nonlocal exchange and correlation used in hybrid functionals allows to reproduce the experimental magnetic coupling constants Jab and Jc as well as the optical gap. Surface calculations performed by both methods using slab models show that the antiferromagnetic (AF) and ferromagnetic (FM) (001) surfaces have lower surface energies than the FM (110) surfac…
Interstitial-oxygen-atom diffusion in MgO.
1996
configuration is the ~111! dumbbell centered at a regular oxygen site, whereas face-centered and cube-centered configurations are higher in energy by 1.45 eV and 3.57 eV, respectively. The~111! configuration isclose in energy to the ~110! configuration, which allows the dumbbell to rotate easily on a lattice site. In allthese four cases the interstitial oxygen atom attracts considerable additional electron density from its nearestregular O
First Principles Calculations of Atomic and Electronic Structure of Ti3+Al- and Ti2+Al-Doped YAlO3
2021
M.G.B. appreciates support from the Chongqing Recruitment Program for 100 Overseas Innovative Talents (grant no. 2015013), the Program for the Foreign Experts (grant no. W2017011), Wenfeng High-end Talents Project (grant no. W2016-01) offered by the Chongqing University of Posts and Telecommunications (CQUPT), Estonian Research Council grant PUT PRG111, European Regional Development Fund (TK141), and NCN project 2018/31/B/ST4/00924. This study was supported by a grant from Latvian Research Council No. LZP-2018/1-0214 (for AIP). Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Program H202…