scholarly journals The Role of Λ-Effective Mass in a Phenomenological Analysis of the Λ-Energy in Hypernuclei

2020 ◽  
Vol 13 ◽  
pp. 277
Author(s):  
C. A. Efthimiou ◽  
M. E. Grypeos ◽  
C. G. Koutroulos
Keyword(s):  
Effective Mass ◽  
Ground State ◽  
State Energy ◽  
Phenomenological Analysis ◽  
Local Effects ◽  
The Past ◽  
Preliminary Account ◽  
Relativistic Treatment ◽  
Non Local

A preliminary account is given of an effort undertaken to allow for the effective mass of the Λ-particle in a phenomenological analysis of existing experimental data for the (ground state) energy of the Λ : EΛ in hypernuclei. The non - relativistic treatment is adopted to describe the motion of the Λ - particle, by considering a central potential well V (r), formed by the nuclear "host" medium of the Λ in the hypernucleus. The Λ - effective mass in the medium is taken to be an r-dependent effective mass mΛ(r) representing approximately some non-local effects in a way suggested in the past. Certain preliminary numerical results are obtained and discussed.

scholarly journals THE ROLE OF THE CARRIER MASS IN SEMICONDUCTOR QUANTUM DOTS

2000 ◽  
Vol 14 (17) ◽  
pp. 1753-1765 ◽  
Author(s):  
M. SINGH ◽  
V. RANJAN ◽  
VIJAY A. SINGH
Keyword(s):  
Quantum Dot ◽  
Effective Mass ◽  
Ground State ◽  
State Energy ◽  
Dimensionless Parameter ◽  
Theoretical Calculations ◽  
Dielectric Coating ◽  
Semiconductor Quantum Dot ◽  
Photoemission Data

In the present work we undertake a re-examination of effective mass theory (EMT) for a semiconductor quantum dot. We take into account the fact that the effective mass (mi) of the carrier inside the dot of radius R is distinct from the mass (m0) in the dielectric coating surrounding the dot. The electronic structure of the quantum dot is determined in crucial ways by the mass discontinuity factor β ≡mi/m0. In this connection we propose a novel quantum scale, σ, which is a dimensionless parameter proportional to β2V0R2, where V0 represents the barrier due to dielectric coating. The scale σ represents a mass modified " strength" of the potential. We show both by numerical calculations and asymptotic analysis that the charge density near the nanocrystallite surface, ρ(r=R), can be large and scales as 1/σ. This fact suggests a significant role for the surface in an EMT based model. We also show that the upshift in the ground state energy is weaker than quadratic, unlike traditional EMT based calculations, and chart its dependence on the proposed scale σ. Finally, we demonstrate that calculations based on our model compare favorably with valence band photoemission data and with more elaborate theoretical calculations.

One-point turbulence structure tensors

2001 ◽  
Vol 428 ◽  
pp. 213-248 ◽  
Author(s):  
S. C. KASSINOS ◽  
W. C. REYNOLDS ◽  
M. M. ROGERS
Keyword(s):  
Turbulence Structure ◽  
Turbulence Statistics ◽  
Local Effects ◽  
Statistical Measures ◽  
Non Local ◽  
The One ◽  
Rate Correlation ◽  
Systematic Framework ◽  
Structure Tensors

The dynamics of the evolution of turbulence statistics depend on the structure of the turbulence. For example, wavenumber anisotropy in homogeneous turbulence is known to affect both the interaction between large and small scales (Kida & Hunt 1989), and the non-local effects of the pressure–strain-rate correlation in the one-point Reynolds stress equations (Reynolds 1989; Cambon et al. 1992). Good quantitative measures of turbulence structure are easy to construct using two-point or spectral data, but one-point measures are needed for the Reynolds-averaged modelling of engineering flows. Here we introduce a systematic framework for exploring the role of turbulence structure in the evolution of one-point turbulence statistics. Five one-point statistical measures of the energy-containing turbulence structure are introduced and used with direct numerical simulations to analyse the role of turbulence structure in several cases of homogeneous and inhomogeneous turbulence undergoing diverse modes of mean deformation. The one-point structure tensors are found to be useful descriptors of turbulence structure, and lead to a deeper understanding of some rather surprising observations from DNS and experiments.

Antibonding σ* orbitals in molecular spectroscopy

1985 ◽  
Vol 63 (7) ◽  
pp. 2032-2043 ◽  
Author(s):  
M. B. Robin
Keyword(s):  
Ground State ◽  
Molecular Spectroscopy ◽  
Atomic Spectroscopy ◽  
High Symmetry ◽  
Giant Resonances ◽  
Molecular Absorption ◽  
Large Molecules ◽  
The Past ◽  
Bond Strengths

This paper discusses the role of σ* antibonding valence MO's in the electronic spectra of large molecules. Using the term value and antishielding concepts, molecular absorption patterns terminating at σ* MO's are systematized and rationalized; the frequencies of such excitations correlate with the ground-state bond strengths of the bonds giving rise to the σ* MO's. In unsaturated systems, the π → σ* and np → σ* excitations can be distinguished on the basis of their term values. Confusion in the past regarding the existence of excitations to σ* relates to the fact that σ* MO's often can be totally mixed into the surrounding sea of Rydberg levels of the same symmetry, and for all practical purposes can cease to exist except as perturbations on the Rydberg levels. For nonpenetrating Rydberg manifolds there is little or no mixing with σ* MO's of the same symmetry, setting the stage for the appearance of valence-shell excitations to σ* in high-symmetry molecules which are analogous to the d → f inner-well giant resonances of atomic spectroscopy.

Ground-State Energy and Effective Mass of the Polaron

1958 ◽  
Vol 111 (3) ◽  
pp. 728-733 ◽  
Author(s):  
Elliott H. Lieb ◽  
Kazuo Yamazaki
Keyword(s):  
Effective Mass ◽  
Ground State Energy ◽  
Ground State ◽  
State Energy

Ground state energy and effective mass of an interface polaron under strong electron-phonon interactions

1993 ◽  
Vol 183 (5-6) ◽  
pp. 418-424 ◽  
Author(s):  
Y.Y. Yeung ◽  
Zu-you Lai ◽  
Shi-wei Gu ◽  
W.S. Li ◽  
T.C. Au-Yeung
Keyword(s):  
Effective Mass ◽  
Ground State Energy ◽  
Ground State ◽  
State Energy ◽  
Strong Electron

scholarly journals On the role of micro-inertia in enriched continuum mechanics

2017 ◽  
Vol 473 (2198) ◽  
pp. 20160722 ◽  
Author(s):  
Angela Madeo ◽  
Patrizio Neff ◽  
Elias C. Aifantis ◽  
Gabriele Barbagallo ◽  
Marco Valerio d’Agostino
Keyword(s):  
Band Gap ◽  
Dynamic Behaviour ◽  
Internal Variable ◽  
Local Effects ◽  
Variable Model ◽  
Complex Behaviour ◽  
Transverse Optic ◽  
Non Local ◽  
New Feature

In this paper, the role of gradient micro-inertia terms η ¯ ∥   ∇ u , t ∥ 2 and free micro-inertia terms η ∥ P , t ∥ 2 is investigated to unveil their respective effects on the dynamic behaviour of band-gap metamaterials. We show that the term η ¯ ∥   ∇ u , t ∥ 2 alone is only able to disclose relatively simplified dispersive behaviour. On the other hand, the term η ∥ P , t ∥ 2 alone describes the full complex behaviour of band-gap metamaterials. A suitable mixing of the two micro-inertia terms allows us to describe a new feature of the relaxed-micromorphic model, i.e. the description of a second band-gap occurring for higher frequencies. We also show that a split of the gradient micro-inertia η ¯ ∥   ∇ u , t ∥ 2 , in the sense of Cartan–Lie decomposition of matrices, allows us to flatten separately the longitudinal and transverse optic branches, thus giving us the possibility of a second band-gap. Finally, we investigate the effect of the gradient inertia η ¯ ∥   ∇ u , t ∥ 2 on more classical enriched models such as the Mindlin–Eringen and the internal variable ones. We find that the addition of such a gradient micro-inertia allows for the onset of one band-gap in the Mindlin–Eringen model and three band-gaps in the internal variable model. In this last case, however, non-local effects cannot be accounted for, which is a too drastic simplification for most metamaterials. We conclude that, even when adding gradient micro-inertia terms, the relaxed micromorphic model remains the best performing one, among the considered enriched models, for the description of non-local band-gap metamaterials.

EXCITON IN ZnO FILM

2007 ◽  
Vol 21 (31) ◽  
pp. 5237-5245 ◽  
Author(s):  
HUA ZHAO ◽  
WEN XIONG ◽  
MENG-ZAO ZHU
Keyword(s):  
Wave Function ◽  
Film Thickness ◽  
Effective Mass ◽  
Ground State Energy ◽  
Ground State ◽  
Quantum Tunneling ◽  
State Energy ◽  
Zno Film ◽  
Mass Approximation ◽  
Exciton Wave Function

The present study variationally calculates the ground state energy and the first excited energy of an exciton in an ZnO film in effective mass approximation. Change of the ground state energy, the first excited energy of an exciton, and radius of the exciton with film thickness are studied, as well as the correction due to the quantum tunneling of the exciton wave function through the film.

GROUND STATE ENERGY LEVELS OF INDIUM ARSENIDE QUANTUM DOTS CALCULATED BY A SINGLE BAND EFFECTIVE MASS MODEL USING REPRESENTATIVE STRAINED INPUT PROPERTIES

2013 ◽  
Vol 27 (16) ◽  
pp. 1350120
Author(s):  
HYUNHO SHIN ◽  
JONG-BONG KIM
Keyword(s):  
Quantum Dots ◽  
Effective Mass ◽  
Indium Arsenide ◽  
Ground State Energy ◽  
Ground State ◽  
State Energy ◽  
Energy Levels ◽  
Single Band ◽  
Hamiltonian Matrix ◽  
Band Model

Representative strained values of effective mass and potential of charge carriers in indium arsenide ( InAs ) quantum dots have been used as input to the complete orthonormal set approach of an effective-mass, single-band, and constant-potential model for the calculation of the ground state energy levels. Even with the avoidance of the diagonalization of the strain Hamiltonian matrix, the single-band-model-calculated ground state energy levels are reasonably refined by the use of representative strained values of potential and effective mass.

USING EVOLUTIONARY ALGORITHM TO CALCULATE THE GROUND-STATE ENERGY OF DOUBLE-ELECTRON ATOMS IN A UNIFORM MAGNETIC FIELD (B ≤ 109G)

2000 ◽  
Vol 11 (01) ◽  
pp. 183-194 ◽  
Author(s):  
LIANJUN LIU ◽  
LI ZHAO ◽  
YOUDONG MAO ◽  
DONG YU ◽  
JINGWEN XU ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Evolutionary Algorithm ◽  
Ground State Energy ◽  
Ground State ◽  
Uniform Magnetic Field ◽  
State Energy ◽  
Electron System ◽  
Energy Calculation ◽  
Double Electron

It is very difficult to calculate the accurate ground-state energies of the double-electron atom like helium in a uniform magnetic field. By using the modified configuration interaction (MCI) method and the evolutionary algorithm (EA), we obtained highly accurate results. We discuss the role of magnetic field in the ground state of the double-electron system and the possibility of variational ground-state energy calculation by using evolutionary algorithm directly. Results show that compared with other algorithms, such as the simplex method, EA is more efficient in calculating atomic energies, and can be used in other fields of physics.

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