About
27
Publications
8,340
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
41
Citations
Introduction
Current institution
Additional affiliations
March 2015 - present
February 2014 - March 2015
Publications
Publications (27)
In this paper the photon-assisted electron motion in a multiquantum well
(MQW) semiconductor heterostructure in the presence of an electric field is
investigated. The time-dependent Schr\"odinger equation is solved by using the
split-operator technique to determine the photocurrent generated by the
electron movement through the biased MQW system. A...
Photocurrents are calculated for a specially designed GaMnAs semiconductor
heterostructure. The results reveal regions in the infrared range of the energy
spectrum in which the proposed structure is remarkably spin-selective. For such
photon energies, the generated photocurrents are strongly spin-polarized.
Application of a relatively small static...
In this work, we have investigated the spin polarization from two-dimensional hole gases (2DHG) formed in p–i–p GaAs/AlAs resonant tunnelling diodes (RTDs) under magnetic field parallel to the tunnel current. We have observed that the polarization degree from the quantum well (QW) and the 2DHG formed at the accumulation layer is highly voltage and...
A semiconductor structure consisting of two coupled quantum wells embedded into the intrinsic region of a {\it p-i-n} junction is proposed to be implemented as an intermediate band solar cell with ratchet state. The localized conduction subband of the right-hand side quantum well is thought as the intermediated band, while the excited conduction su...
A semiconductor heterostructure consisting of two quantum wells, one of them magnetically doped, is proposed for the generation of spin currents by two lasers tuned at the resonances formed between two lowest energy states (1 and 2) and the continuum (3), which are set by design to be in a λ like configuration. By numerically simulating the propose...
Gold and silver alloys present innovative possibilities for engineering metals with unique optical properties. However, earlier theoretical methods have obtained the permittivity of alloys by linearly interpolating the response of their pure counterparts or averaging out the spatially dependent anisotropic results of small cells owing to their tetr...
Fontes de energia renovável estão mudando a forma como vivemos e um dos exemplos mais promissores é o uso de células solares para capturar energia. Com a crescente demanda por energia limpa, é crucial entender os conceitos físicos subjacentes ao funcionamento das células solares. No entanto, isso pode ser um desafio, mesmo para estudantes universit...
**https://loja.uiclap.com/titulo/ua44165/**
A Física e a computação são áreas emaranhadas. Em 'Física Computacional usando Python', os leitores são conduzidos por uma jornada que entrelaça os princípios fundamentais da programação com a riqueza conceptual da Física. Este livro não apenas explora os conceitos essenciais da codificação, mas também d...
With the advent of near-term quantum computers, it is now possible to simulate solid-state properties using quantum algorithms. By an adequate description of the system’s Hamiltonian, variational methods enable to fetch of the band structure and other fundamental properties as transition probabilities. Here, we describe semiconductor structures of...
he engineering of optoelectronic devices is closely related to the dependency of quantum wells properties with structural parameters. Obtaining their properties relies on solving Schrödinger’s equation employing several degrees of approximation as the influence of band non-parabolicity effects. In general, the more sophisticated the approximations...
With the advent of near-term quantum computers, the simulation of properties of solids using quantum algorithms becomes possible. By an adequate description of the system's Hamiltonian, variational methods enable to fetch the band structure and other fundamental properties as transition probabilities. Here, we use k·p Hamiltonians to describe semic...
A física de materiais tem sido desenvolvida ao longo das últimas décadas com grande ajuda de simulações digitais nos supercomputadores que temos disponíveis no século atual. Porém, é certo que há conhecidos limites de até onde podem chegar essas simulações e quais sistemas somos capazes de simular em um tempo de computação eficaz. A computação quân...
Classical quantification of gastric emptying (GE) and orocaecal transit (OCT) based on half-life time T50, mean gastric emptying time (MGET), orocaecal transit time (OCTT) or mean caecum arrival time (MCAT) can lead to misconceptions when analyzing irregularly or noisy data. We show that this is the case for gastrointestinal transit of control and...
Quantum computers are a reality. They represent the next step in computational performance with practical implications that will soon impact our lives. Yet standing at an initial stage called NISQ computation [1] it is already possible to create and run a plethora of circuits and algorithms using qubits instead of bits. Quantum computers are an end...
In this work, we demonstrate a different approach to the calculation of the dark current of quantum well-infrared photodetectors (QWIP), with a modified version of Levine’s method. A quantum well-dependent transmission probability was proposed and evaluated. As a result, the model accurately reproduced the experimental behavior of the photodetector...
The technological advances from specific studies in the area of optoelectronic semiconductor devices has increased significantly in the last decades due to the great demand for clean and renewable energy fonts. Thus, the growing search for energetic fonts demands a continuous increase in the electric current generation efficiency of these cells. Am...
A semiconductor structure consisting of two coupled quantum wells embedded into the intrinsic region of a {\it p-i-n} junction is proposed to be implemented as an intermediate band solar cell with ratchet state. The localized conduction subband of the right-hand side quantum well is thought as the intermediated band, while the excited conduction su...
Dark current noise in InGaAs/InAlAs quantum well infrared photodetectors has been investigated as a function of temperature and bias voltage. From the current noise dependence on these parameters the noise gain has been determined.
In the present thesis, we realize a computational modeling of semiconductor structures based on multiple quantum wells with filter barriers and on quantum wells with semiconductor diluted magnetic layers. We numerically solve the time-dependent Schrödinger s equation within the effective mass approximation, using the Split Operator method. Through...
Time dependent calculations of induced photocurrents are presented for
ZnMnSe semiconductor nanostructures under the action of a static
magnetic field of a few Tesla. The study shows the existence of spectral
domains in the THz range for which the spin polarization in the
photocurrent is strongly sensitive to static biases applied in the
growth dir...
The aim of this work was to complement the studies of the mechanisms of control of the degree of circular polarization of emission from resonant tunneling diodes p-type (RTD) by analyzing the optical properties and transport of this type of structure. We focus primarily on the influence of the width of quantum well to these properties and the possi...
Questions
Questions (2)
Hello all,
I'm starting using quantum espresso aiming to work with metallic alloys. After a basic search I was able to verify that the phonon package of QE gives as output the tridimensional dielectric constant of the simulated system. However, I didn't find information about its frequency dependence. Could anyone help me or even give some references concerning the task?
Thanks in advance!!
Dear all,
I'm currently working with DFT using quantum espresso. I have to determine the plane wave energy cutoff for a system with a big number of atoms. Is it possible to get such an energy by a smaller representative system, in order to speed up the process?
