Three-antenna two-dimensional imaging correlation radiometer: concept and preliminary results

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The Young Modulus of Black Strings and the Fine Structure of Blackfolds

We explore corrections in the blackfold approach, which is a worldvolume theory capturing the dynamics of thin black branes. The corrections probe the fine structure of the branes, going beyond the approximation in which they are infinitely thin, and account for the dipole moment of worldvolume stress-energy as well as the internal spin degrees of freedom. We show that the dipole correction is induced elastically by bending a black brane. We argue that the long-wavelength linear response coefficient capturing this effect is a relativistic generalization of the Young modulus of elastic materials and we compute it analytically. Using this we draw predictions for black rings in dimensions greater than six. Furthermore, we employ our corrected blackfold equations to various multi-spinning black hole configurations in the blackfold limit, finding perfect agreement with known analytic solutions.Comment: v1: 28 pages + appendices. v2: Important sign corrections in sec. 3. Other minor correction

Chemistry on quantum computers with virtual quantum subspace expansion

Several novel methods for performing calculations relevant to quantum chemistry on quantum computers have been proposed but not yet explored experimentally. Virtual quantum subspace expansion [T. Takeshita et al., Phys. Rev. X 10, 011004 (2020)] is one such algorithm developed for modeling complex molecules using their full orbital space and without the need for additional quantum resources. We implement this method on the IBM Q platform and calculate the potential energy curves of the hydrogen and lithium dimers using only two qubits and simple classical post-processing. A comparable level of accuracy would require twenty qubits with previous approaches. We also develop an approach to minimize the impact of experimental noise on the stability of a generalized eigenvalue problem that is a crucial component of the algorithm. Our results demonstrate that virtual quantum subspace expansion works well in practice

Designing oxynitride nanostructured thin films to enhance europium white light emission for efficient solid state emitters

CLEO®/Europe-EQEC 2015, Munich (ICM), Germany, June 21st, - 25th, 2015; http://2015.cleoeurope.org/In the present work we study the visible light emission of europium (Eu) ions embedded in two different matrices (amorphous aluminum oxide (a-Al2O3) and ceramic SiAlON) as a function of the Eu distribution and concentration. Eu-doped thin films were produced using the pulsed laser deposition technique by the alternating ablation of the matrix target and the Eu target; as a result nanostructured Eu-doped multilayers were formed. The Eu in-depth distribution was modified by varying the host inter-layer thickness, which ranged from 1 to 15 nm, and the Eu content per layer was modified by varying the number of pulses on the Eu target. Under UV excitation (355 nm), the as-deposited films of both matrices showed a broadband emission (FWHM ¿200 nm), that has been related to the superposition of the 5d levels to the 4f levels of the Eu2+, which is rarely found in pure oxides. This broad emission was further enhanced keeping the same spectral distribution upon annealing treatments up to 500 oC for the a-Al2O3 (Fig. 1a) and 700 oC for the SiAlON (Fig. 1c). However for samples with higher Eu content and at the higher annealing temperatures the spectral shape emission changed and the emission spectra showed narrow and well-defined emission peaks. These have been identified as resulting from the 4f ¿ 4f transitions of Eu3+ (Fig. 1b). Therefore, it has been found that two distinct and efficient Eu-related emissions can be obtained by a suitable design of the Eu distribution and concentration. This is due to a change of oxidation state of Eu in the films, which will be discussed. These Eu-doped films have a high potential for the development of either solid state lighting LEDs with broadband emission, or integrated lasers with narrow emission lines. Acknowledgements. This work has been financially supported by the Spanish Ministry of Economy and Competitiveness through the project TEC2012_38901-C02-01. I.C. acknowledges the financial support through JAE-Pre-2011_00578. A.M. acknowledges the financial support through BES-2013-062593.This work has been financially supported by the Spanish Ministry of Economy and Competitiveness through the project TEC2012_38901-C02-01. I.C. acknowledges the financial support through JAE-Pre-2011_00578. A.M. acknowledges the financial support through BES-2013-062593.Peer Reviewe

Trasplante de Pelo en la Alopecia Fibrosante Frontal: ¿Parte de la Solución?

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Black Branes in a Box: Hydrodynamics, Stability, and Criticality

We study the effective hydrodynamics of neutral black branes enclosed in a finite cylindrical cavity with Dirichlet boundary conditions. We focus on how the Gregory-Laflamme instability changes as we vary the cavity radius R. Fixing the metric at the cavity wall increases the rigidity of the black brane by hindering gradients of the redshift on the wall. In the effective fluid, this is reflected in the growth of the squared speed of sound. As a consequence, when the cavity is smaller than a critical radius the black brane becomes dynamically stable. The correlation with the change in thermodynamic stability is transparent in our approach. We compute the bulk and shear viscosities of the black brane and find that they do not run with R. We find mean-field theory critical exponents near the critical point.Comment: 23 pages, 3 figures. v2: added comments on first-order phase transitio