We propose an AdS$\times$S factorization formula at the level of the generating function for correlators with arbitrary Kaluza-Klein configurations, and implement it in the supergravity limit of $\mathcal{N}=4$ super Yang-Mills. By incorporating this mechanism into Mellin space bootstrap, together with an observed $\mathbb{Z}_2$ symmetry under AdS $\leftrightarrow$ S, we manage to...
The theory of open quantum systems is one of the most essential tools for the development of quantum technologies. A particular area of interest is in the optical response of solid state systems, where dissipation is introduced phenomenologically through the relaxation time approximation and its effects are usually gauged perturbatively . Here, we obtain the analytical solution for a general...
Meteorological re-initialization with chemistry recycling and spectral nudging above the planetary boundary layer have been frequently used simulation techniques in online coupled meteorology-atmospheric chemistry regional models to study aerosol-radiation-cloud interactions. While these model-running methods may reduce meteorological drifting from the observed atmospheric state, their impact...
Weyl nodal loop semimetals are topological semimetals where the valence and conduction bands linearly touch along one dimensional loops in momentum space. A manifestation of their non-trivial topology is the presence of zero energy surface states, induced by chiral symmetry, on surfaces parallel to the loop plane. Unlike their insulator counterparts, these exotic phases may be unstable to...
Non-invasive, high-resolution detection of neuronal activity remains a key challenge in neuroscience and bioimaging. Nitrogen-vacancy (NV) center magnetometry is a promising quantum sensing technology capable of detecting the weak magnetic fields generated by neuronal currents.A key requirements to obtain good quantum sensors with optimal properties is the fabrication. While ion implantation...
The production of functional materials derived from dipeptides is gaining significant attention in bionanotechnology due to their biocompatibility, structural rigidity, versatile morphologies, and ease of functionalization and synthesis [1]. Cyclodipeptides are an emerging group of ring-shaped dipeptides, that exhibit the unique ability to dimerize into quantum dots which, self-assemble into...
Domain walls are the simplest type of topological defects formed at cosmological phase transitions, and one of the most constrained. Their studies typically assume a quartic double well potential, but this model is not fully representative of the range of known or plausible particle physics models. Here we study the cosmological evolution of domain walls in two other classes of potentials. The...
Ferroelectric (FE) zirconium oxide (ZrO2) thin films are a promising alternative to hafnium oxide (HfO2) for low-power, high-speed memory devices due to their greater natural abundance and lower crystallization temperature. Ferroelectricity arises from the metastable polar orthorhombic (o-, s.g. Pca21) phase, making its stabilization central to obtaining functional FE properties....
We investigate, both experimentally and theoretically, photoluminescence (PL) spectra of J-aggregates (JC1) covering silver nanorods (AgNRs). When these hybrid nanoparticles (J-agg@AgNRs) are deposited on the surface of a spherical microcavity (MC), their non-resonantly excited PL spectra show a series of sharp resonances in the broad spectral range of 550 -- 650 nm, characterized by Fano-type...
Guiding light in hollow core waveguides is a key direction in fiber optics, offering transformative applications. Yet, fabrication limits have prevented their full use in planar systems. Here, we introduce a fiber-integrated hollow-core waveguide that apply the antiresonant guiding principle to planar technology through 3D nanoprinting. High-aspect-ratio structures are printed directly on...
Optical computing has long been regarded as a promising avenue for fast and energy-efficient information processing. The field has already made significant contributions to modern technology by enhancing performance in specialized tasks such as matrix-matrix multiplication, Fourier transforms, and convolutions. Despite these successes, the development of an optical algorithm capable of...
Optical computing has long been regarded as a promising avenue for fast and energy-efficient information processing. The field has already made significant contributions to modern technology by enhancing performance in specialized tasks such as matrix-matrix multiplication, Fourier transforms, and convolutions. Despite these successes, the development of an optical algorithm capable of...
Several studies have now shown that the polymorphism of water also extends to ambient conditions, the stability and size of the liquid tetrahedrally domains (LDL) decrease upon heating, with significant implications for biological function and nanotechnology [1,2].
In our new work, we demonstrate that the onset temperature of LDL domain fluctuations in ambient liquid water at the surface of...
Silica based optical fibers composed of different commercial and specialty fibers spliced together for the measurement of physical parameters were developed. These structures were interfaced with self-written waveguides (SWWs) based on UV curable polymers, forming a thin Fabry-Perot (FP) polymer cavity in front of the fiber tip after UV exposure from the fiber structure itself. This method was...
Microcystin-LR (MC-LR) is a biotoxin produced by several cyanobacteria. It is present in different aquatic environments and is not easily removed from water by conventional treatments. In this way, humans are primarily exposed to MC-LR via drinking water, creating multiple health risks such as poisoning, hepatoxicity, tumor promotion and reproductive issues [1], [2]. Consequently, the World...
We present the building blocks of an energy-efficient on-chip platform for neural network applications based on III-V semiconductor nanopillar arrays. This approach draws inspiration from insect eyes and their neuronal architecture, as they allow for remarkable capabilities to extract and process information from the surrounding environment with extremely low energy consumption.
A...
A interação entre clima e meteorologia influencia profundamente diversos setores, em particular a agricultura, sendo a viticultura um exemplo de destaque em Portugal. Apesar da sua dimensão relativamente pequena, o país possui numerosas regiões vitivinícolas, cada uma com características próprias de clima, solo, castas e tradições. As alterações climáticas e as condições meteorológicas...
This study examines how inflationary dynamics are affected by $f(R)$ theories with a non-minimal coupling between matter and curvature. Both positive and negative corrections to the minimal coupling of General Relativity are considered, and a robust numerical method is developed that evolves the metric and the inflaton field in this modified theory beyond slow-roll. Through a stability...
GW observations in the last decade have reinforced the Kerr BH paradigm, but these conclusions rely on waveform catalogs dominated by Kerr BH. Expanding the diversity of modeled sources is essential to uncover potential new physics. However, only bodies whose stability is known can become viable alternatives. Here, we study the stability of Q-hairy BHs, solutions in the Einstein-Maxwell-Scalar...
We examine how a cosmological stochastic gravitational-wave background could interfere with the standard procedure used in LISA data analysis to subtract bright, individually detectable Galactic binaries. This subtraction step is essential for revealing weaker, unresolved signals, but the presence of an additional cosmological background can distort the outcome. We quantify this effect by...
We study the Higgs boson decay into dark matter (DM) in the framework of freeze-in at stronger coupling. Even though the Higgs-DM coupling is significant, up to order one, DM does not thermalize due to the Boltzmann suppression of its production at low temperatures. We find that this mechanism leads to observable Higgs decay into invisible final states with the branching fraction of 10% and...
Geomagnetic storms during the declining phase of the solar cycle 24 were studied using the total electron content (TEC) data obtained from three geodetic receivers located in Portugal: Lisbon (Continental Portugal), Furnas (Azores) and Funchal (Madeira). Two of the receivers (Lisbon and Furnas) are located at about the same latitude (~39ºN) while the third receiver (Funchal, ~33ºN) is...
In this study, we investigate the nanoscopic structural properties of Ca2Mn1-xTixO4 Ruddlesden-Popper (RP) perovskites combining experimental and computational approaches. Atomic-scale measurements were conducted at ISOLDE/CERN with Perturbed Angular Correlation (PAC) spectroscopy with 111mCd (48 min) probes at substitutional Ca-sites [1]. This method has provided insights into structural...
In this work is treated the employment of Machine Learning techniques as statistical data analysis tool in the research field of high energy physics.
The quantum field theory of Standard Model remains, today, the most faithful description of the fundamental behavior of nature: most of the predictions about the fundamental matter composition and its interaction laws have found experimental...
We investigate the space of massive two-dimensional theories with a global U(N) symmetry and no bound states. Following S-matrix bootstrap principles, we establish rigorous bounds on the space of consistent 2 → 2 scattering amplitudes. The allowed regions exhibit rich geometric features with integrable models appearing at special points along the boundary.
Generic extremal amplitudes display...
Zhu et al. [1] report that the CsNdNb₂O₇ system undergoes two phase transitions: a polar-to-antipolar structural change at 625 K followed by a transition to the aristotype at 800 K, resulting in three distinct phases— P21am (#26), C2/m (#12), and P4/mmm (#123). Their study attributes these transitions to rotations and tilts of NbO₆ octahedra, which not only stabilize the polar ferroelectric...
Skin cancer is the most common of all cancers and can be divided in three types: basal cell carcinoma, squamous cell carcinoma, and melanoma, the latter being the most aggressive. Current therapies for melanoma present several drawbacks, which highlights the need for new therapeutic approaches.
Electroactive, biocompatible, and biodegradable polymers, such as...
INTRODUCTION
Rare-earth orthoferrites, such as NdFeO3, exhibit intricate magnetic and structural transitions, making them compelling for spintronics and optoelectronic applications. NdFeO 3 undergoes a spin-reorientation transition (SRT) between 170 K and 100 K, accompanied by symmetry changes from orthorhombic (Pbnm) to monoclinic (P2 ₁/c). This work explores these phenomena and their...
A holographic Conformal Field Theory (CFT) is characterized by a sparse spectrum with a large gap, that ensures that no higher spin field exist at low energies, and a large central charge, which implies a Fock space structure in the spectrum of local operators. But these scales are also related to interesting physics, namely extended objects in the gravitational theory. Using the effective...
Atmospheric rivers (ARs) are long, transient, and narrow corridors of strong transport of water vapour that, on average, carry more than double of the Amazon River flow. They are an important component of Earth’s hydrological cycle transporting moisture and heat from the tropics to higher latitudes, often leading to intense precipitation. Recent studies found that ARs may also be associated...
In High Energy Physics, when testing theoretical models of new physics against experimental results, the customary approach is to simply sample random points from the parameter space of the model, calculate their predicted values for the desired observables and compare them to experimental data. However, due to the typically large number of parameters in these models, this process is highly...
Gravitational wave data are often contaminated by transient noise artifacts, called "glitches", which can mimic astrophysical signals and interfere with their detection. When represented in the time-frequency domain, glitches show peculiar morphologies, which allow their categorization into distinct families. As it is expected that glitches which share a similar morphology also share the same...
