663 citations · 1k across the 19 of their papers we have counts for
22 papers
Energy Transfer and Coherence in Coupled Oscillators with Delayed Coupling: A Classical Picture for Two-Level Systems
Fahhad H Alharbi, Abdelrahman S Abdelrahman, Abdullah M Alkathiry +1
The Frimmer-Novotny model to simulate two-level systems by coupled oscillators is extended by incorporating a constant time delay in the coupling. The effects of the introduced del…
On the Kinetic Energy Density Functional: The Limit of the Density Derivative Order
Abdulaziz H. Al-Aswad, Fahhad H. Alharbi
Within ``orbital-free'' density functional theory, it is essential to develop general kinetic energy density (KED), denoted as . This is usually done by empirical co…
Psitrum: An Open Source Simulator for Universal Quantum Computers
Mohammed Alghadeer, Eid Aldawsari, Raja Selvarajan +3
Quantum computing is a radical new paradigm for a technology that is capable to revolutionize information processing. Simulators of universal quantum computer are important for und…
Extending Shannon's Ionic Radii Database Using Machine Learning
Ahmer A. B. Baloch, Saad M. Alqahtani, Faisal Mumtaz +3
In computational material design, ionic radius is one of the most important physical parameters used to predict material properties. Motivated by the progress in computational mate…
Dark states and delocalization: competing effects of quantum coherence on the efficiency of light harvesting systems
Zixuan Hu, Gregory S. Engel, Fahhad H. Alharbi +1
Natural light harvesting systems exploit electronic coupling of identical chromophores to generate efficient and robust excitation transfer and conversion. Dark states created by s…
An Efficient Descriptor Model for Designing Materials for Solar Cells
Fahhad H Alharbi, Sergey N Rashkeev, Fedwa El-Mellouhi +3
An efficient descriptor model for fast screening of potential materials for solar cell applications is presented. It works for both excitonic and non-excitonic solar cells material…
Kinetic Energy Density Functionals by Axiomatic Approach
Sabre Kais, Fahhad H Alharbi
An axiomatic approach is herein used to determine the physically acceptable forms for general -dimensional kinetic energy density functionals (KEDF). The resulted expansion capt…
Reduced work function of graphene by metal adatoms
Merid Legesse, Fedwa El Mellouhi, El Tayeb Bentria +4
In this paper, the work function of graphene doped by different metal adatoms and at different concentrations is investigated. Density functional theory is used to maximize the red…
Hydrogen Bonding: A Mechanism for Tuning Electronic and Optical Properties of Hybrid Organic-Inorganic Frameworks
Fedwa El-Mellouhi, El Tayeb Bentria, Asma Marzouk +3
Here we demonstrate that significant progress in this area may be achieved by introducing structural elements that form hydrogen bonds with environment. Considering several example…
Enhancing Intrinsic Stability of Hybrid Perovskite Solar Cell by Strong, yet Balanced, Electronic Coupling
Fedwa El-Mellouhi, El Tayeb Bentria, Sergey N Rashkeev +2
In the past few years, the meteoric development of hybrid organic--inorganic perovskite solar cells (PSC) astonished the community. The efficiency has already reached the level nee…
Correction to kinetic energy density using exactly solvable model
Alexey Sergeev, Raka Jovanovic, Sabre Kais +1
An accurate non-gradient-expansion based correction to Thomas--Fermi is developed using solvable model. The used model is a system of non-interacting electrons moving independe…
Electron Localization and Energy Levels' Oscillations Induced by Controlled Deformation
Fahhad H. Alharbi, Pablo Serra, Marcelo Carignano +1
Manipulating energy levels while controlling the electron localization is an essential step for many applications of confined systems. In this paper we demonstrate how to achieve e…
Domain Walls Conductivity in Hybrid Organometallic Perovskites: The Key of CH3NH3PbI3 Solar Cell High Performance
Sergey N. Rashkeev, Fedwa El-Mellouhi, Sabre Kais +1
The past several years has witnessed a surge of interest in organometallic trihalide perovskites, which are at the heart of the new generation of solid-state solar cells. Here, we…
Cuckoo Search Inspired Hybridization of the Nelder-Mead Simplex Algorithm Applied to Optimization of Photovoltaic Cells
Raka Jovanovic, Sabre Kais, Fahhad H. Alharbi
A new hybridization of the Cuckoo Search (CS) is developed and applied to optimize multi-cell solar systems; namely multi-junction and split spectrum cells. The new approach consis…
Convergent sum of gradient expansion of the kinetic-energy density functional up to the sixth order term using Pade approximant
A. Sergeev, R. Jovanovic, S. Kais +1
The gradient expansion of the kinetic energy functional, when applied for atoms or finite systems, usually grossly overestimates the energy in the fourth order and generally diverg…
Delocalized Quantum States Enhance Photocell Efficiency
Yiteng Zhang, Sangchul Oh, Fahhad H. Alharbi +2
The high quantum efficiency of photosynthetic complexes has inspired researchers to explore new routes to utilize this process for photovoltaic devices. Quantum coherence has been…
Revealing the role of organic cations in hybrid halide perovskites CH3NH3PbI3
Carlo Motta, Fedwa El Mellouhi, Sabre Kais +3
The hybrid halide perovskite CHNHPbI has enabled solar cells to reach an efficiency of about 18\%, demonstrating a pace for improvements with no precedents in the…
Theoretical Limits of Photovoltaics Efficiency and Possible Improvements by Intuitive Approaches Learned from Photosynthesis and Quantum Coherence
Fahhad H Alharbi, Sabre Kais
In this review, we present and discussed the main trends in photovoltaics with emphasize on the conversion efficiency limits. The theoretical limits of various photovoltaics device…
Efficient method for localized functions using domain transformation and Fourier sine series
Raka Jovanovic, Sabre Kais, Fahhad H. Alharbi
An efficient approach to handle localized states by using spectral methods (SM) in one and three dimensions is presented. The method consists of transformation of the infinite doma…
Coupled plasmon - phonon excitations in extrinsic monolayer graphene
V. U. Nazarov, F. Alharbi, T. S. Fisher +1
The existence of an acoustic plasmon in extrinsic (doped or gated) monolayer graphene was found recently in an {\it ab initio} calculation with the frozen lattice [M. Pisarra {\it…
Quantum Confinement and Negative Heat Capacity
Pablo Serra, Marcelo Carignano, Fahhad Alharbi +1
Thermodynamics dictates that the specific heat of a system is strictly non-negative. However, in finite classical systems there are well known theoretical and experimental cases wh…
Quantum criticality analysis by finite size scaling and exponential basis sets
Fahhad H Alharbi, Sabre Kais
We combine the finite size scaling method with the meshfree spectral method to calculate quantum critical parameters for a given Hamiltonian. The basic idea is to expand the exact…