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Quantum Well

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lightbulbAbout this topic
A quantum well is a potential energy structure that confines charge carriers, such as electrons and holes, in a thin layer of semiconductor material, allowing quantized energy levels. This confinement leads to unique electronic and optical properties, making quantum wells essential in the development of various semiconductor devices, including lasers and photodetectors.
lightbulbAbout this topic
A quantum well is a potential energy structure that confines charge carriers, such as electrons and holes, in a thin layer of semiconductor material, allowing quantized energy levels. This confinement leads to unique electronic and optical properties, making quantum wells essential in the development of various semiconductor devices, including lasers and photodetectors.

Key research themes

1. How can quantum algorithms be used to estimate energy states in quantum well potentials, and what are the practical challenges of implementation on current quantum hardware?

This theme focuses on the application of quantum computing techniques, specifically quantum phase estimation and iterative phase estimation algorithms, to calculate energy eigenvalues of quantum well systems, such as finite square-well potentials. It addresses both the algorithmic development and the practicalities of executing these algorithms on contemporary quantum devices like IBM quantum computers, thereby linking theoretical quantum simulations with experimental quantum information processing capabilities.

Key finding: This work successfully implements quantum phase estimation and iterative phase estimation algorithms to find ground and first excited state energies of a particle in a finite square well potential, executed both on IBM... Read more

2. What analytic and geometric methods provide exact or interpretable solutions for energy levels in quantum finite square wells, and how can special functions like the Lambert W function enhance understanding?

This theme investigates advanced analytic techniques for solving the bound state energy level problem in finite square-well quantum mechanics. Methods include geometric-analytic approaches exploiting conformal mappings and the Lambert W function to move beyond numerical or graphical solution methods. These approaches deliver exact closed-form descriptions, provide insights into sensitivity to potential parameters, and assist in designing quantum devices with tunable quantum well characteristics.

Key finding: The paper introduces a novel geometric-analytic method using conformal mappings and the Lambert W function to derive exact solutions for the allowed energy levels of a bound particle in a 1D finite square well. This approach... Read more
Key finding: By replacing idealized discontinuous square-well potentials with trapezoidal wells and investigating the limit where the slopes become vertical, this study rigorously proves the standard assumptions about eigenfunction... Read more
Key finding: Highlighting an overlooked solution involving spherical Neumann functions, this paper corrects the infinite spherical well solution by enforcing self-adjointness of the Hamiltonian, leading to non-zero radial probability... Read more

3. How do engineered quantum well structures and external fields influence the electronic and optical properties relevant for device applications such as lasers and photodetectors?

This theme encompasses the study of quantum well heterostructures with complex potential profiles—such as harmonic-Gaussian double quantum wells, graded quantum barriers, and multilayer quantum wells—and examines how these engineered potentials, in combination with external influences like intense laser fields or magnetic fields, modulate electronic states, optical transition energies, nonlinear optical properties, and device performance metrics including radiative recombination and quantum efficiency. The goal is to connect quantum well design with practical advancements in optoelectronics.

Key finding: Using an effective mass approximation and considering an applied magnetic field, this study models electronic structure and optical responses of symmetric and asymmetric harmonic-Gaussian double quantum wells. It reveals how... Read more
Key finding: Simulation of electron blocking layer (EBL)-free GaN/AlGaN LED structures with graded aluminum composition quantum barriers demonstrates significantly reduced electron leakage and enhanced hole injection, yielding a 136.7%... Read more
Key finding: Employing a semi-relativistic wave equation within the effective mass approximation, this study investigates two-level qubits in GaAs, GaN, and AlN quantum wells, revealing material-dependent oscillation periods and... Read more

All papers in Quantum Well

The electronic band structure of Ag films deposited on two quasiperiodic templates has been explored by angle-resolved photoemission. Direct observation of sp-derived quantum well states in the metallic layers confirms the mechanism of... more
A systematic study of GaAs/In Ga& "As single quantum wells is performed in two sets of samples with different alloy concentrations (namely, x =9%%uo and 18.5%%u&) and well thicknesses ranging from 15 to 0 250 A. These samples are grown by... more
We report on a novel quantum well saturable absorber device whose measured response time of 1.5 psec and contrast of at least 4 dB make it suitable for all-optical extinction ratio enhancement at 160 Gbitls.
Ultrafast switching with low energies is demonstrated using InP photonic crystal nanocavities embedding InGaAs surface quantum wells heterogeneously integrated to a silicon on insulator waveguide circuitry. Thanks to the engineered... more
The optical and structural properties of Charge Asymmetric Resonance Tunneling (CART) structure InGaN/GaN multiquantum wells (MQWs) grown on sapphire by metalorganic chemical vapor deposition (MOCVD) have been investigated by optical... more
The anomalous Berthelot-type optical properties of quaternary AlInGaN heterostructure with different quantum well pairs have been investigated systematically in this study. A microscopic model based on the luminescence observations of a... more
The electronic band structure of different alkyl/Si͑111͒ self-assembled monolayers ͑SAMs͒ was investigated using photoelectron spectroscopy ͑PES͒ with variable photon energy. We observe a significant dispersion in the valence-band spectra... more
The strong light-matter interaction in ZnO-embedded microcavities has received great attention in recent years, due to its ability to generate the robust bosonic quasiparticles, exciton-polaritons, at or above room temperature. This... more
Here we report the first realization of a current injection microcavity GaN exciton-polariton light emitting diode (LED) operating under room temperature (RT). The hybrid microcavity structure consists of InGaN/GaN quantum wells... more
In this paper, we study the existence and the nonexistence of solutions for a new class of p(x)-curl systems arising in electromagnetism. This work generalizes some results obtained in the p-curl case. There seems to be no results on the... more
In this paper, we study the existence and the nonexistence of solutions for a new class of p(x)-curl systems arising in electromagnetism. This work generalizes some results obtained in the p-curl case. There seems to be no results on the... more
In this paper, we study the existence and the nonexistence of solutions for a new class of p(x)-curl systems arising in electromagnetism. This work generalizes some results obtained in the p-curl case. There seems to be no results on the... more
This study develops a variational approach to calculate the binding energy of a shallow hydrogenic impurity in a n-doped In0.53Ga0.47As/InP single quantum well. Using a proper trial wavefunction, both Schrödinger and Poisson equations... more
This paper presents the design and simulation of an InGaAs/GaAsSb single quantum well (SQW) structure for optical communication applications at 300 K. The electronic band structure, carrier transport, and optical gain characteristics of... more
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or... more
InAs nanostructures formed on InP substrates allow the realization of devices working in telecommunication wavelength range between 1.4 and 1.65 µm. However due to the low lattice mismatch existing between InAs and InP, the self... more
Using first-principles calculations within density functional theory, we study Friedel oscillations (FOs) in the electron density at different metal surfaces and their influence on the lattice relaxation and stability of ultrathin metal... more
We show theoretically the possibility of excitation of a special class of two-frequency solitons, sustained by the nonlinearity provided by the nonradiative intervalence band coherence between heavy-hole and light-hole excitonic... more
Periodic structures resonantly coupled to excitonic media allow the existence of extra intragap modes ('Braggoritons'), due to the coupling between Bragg photon modes and 3D bulk excitons. This induces unique and unexplored dispersive... more
We show theoretically the possibility of excitation of a special class of two-frequency solitons, sustained by the nonlinearity provided by the nonradiative intervalence band coherence between heavy-hole and light-hole excitonic... more
We suggest a scheme for the excitation and amplification of surface plasmon polaritons (SPPs) along the interface between metal and semiconductor quantum well (SQW), employing a four-wave mixing (FWM) process. The SQW consists of... more
We address the electronic structure of quantum wells in polar-nonpolar oxide heterojunction systems focusing on the case of non-polar BaVO3 wells surrounded by polar LaTiO3 barriers. Our discussion is based on a density functional... more