Decrease in the injection efficiency and generation of midgap states in UV-C LEDs: a model based on rate equations

ABSTRACTSpin dependent photoconductivity measurements provide evidence for the existence of tunneling transitions from localized tail states into the dangling bond recombination centers. These processes can be included approximately into the conventional model based on rate equations. Satisfactory values for the activation energy of the photoconductivity at low temperatures are obtained. Our model produces thermal quenching and an enhancement of the photoconductivity with rising dark Fermi level.

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A laser diode model based on temperature dependent rate equations

IEEE Photonics Technology Letters ◽

10.1109/68.43375 ◽

1989 ◽

Vol 1 (11) ◽

pp. 356-359 ◽

Cited By ~ 20

Author(s):

D.M. Byrne ◽

B.A. Keating

Keyword(s):

Laser Diode ◽

Rate Equations ◽

Temperature Dependent ◽

Model Based ◽

Dependent Rate

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Modeling the degradation mechanisms of AlGaN-based UV-C LEDs: from injection efficiency to mid-gap state generation

Photonics Research ◽

10.1364/prj.401785 ◽

2020 ◽

Vol 8 (11) ◽

pp. 1786

Author(s):

F. Piva ◽

C. De Santi ◽

M. Deki ◽

M. Kushimoto ◽

H. Amano ◽

...

Keyword(s):

Degradation Mechanisms ◽

Injection Efficiency ◽

State Generation ◽

Uv C ◽

Gap State

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Representation, abstraction, and simple-minded sophisticates

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002942 ◽

2020 ◽

Vol 43 ◽

Author(s):

Peter Dayan

Keyword(s):

Decision Theory ◽

Predictive Coding ◽

Bayesian Decision Theory ◽

Bayesian Decision ◽

Model Based ◽

Model Free

Abstract Bayesian decision theory provides a simple formal elucidation of some of the ways that representation and representational abstraction are involved with, and exploit, both prediction and its rather distant cousin, predictive coding. Both model-free and model-based methods are involved.

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Dielectronic Recombination in the Average-Atom Model

International Astronomical Union Colloquium ◽

10.1017/s0252921100107730 ◽

1988 ◽

Vol 102 ◽

pp. 215

Author(s):

R.M. More ◽

G.B. Zimmerman ◽

Z. Zinamon

Keyword(s):

Detailed Balance ◽

Systematic Errors ◽

Dielectronic Recombination ◽

Rate Equations ◽

Strong Correlations ◽

Dense Plasmas ◽

Atom Model ◽

New Feature ◽

Average Atom Model ◽

Attachment Process

Autoionization and dielectronic attachment are usually omitted from rate equations for the non–LTE average–atom model, causing systematic errors in predicted ionization states and electronic populations for atoms in hot dense plasmas produced by laser irradiation of solid targets. We formulate a method by which dielectronic recombination can be included in average–atom calculations without conflict with the principle of detailed balance. The essential new feature in this extended average atom model is a treatment of strong correlations of electron populations induced by the dielectronic attachment process.

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On the interpretation of dislocation-loop growth during in-situ high-voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017579x ◽

1990 ◽

Vol 48 (4) ◽

pp. 532-533

Author(s):

E. Holzäpfel ◽

F. Phillipp ◽

M. Wilkens

Keyword(s):

Point Defect ◽

Rate Equations ◽

Rate Theory ◽

Dislocation Loops ◽

High Voltage Electron Microscopy ◽

Vacancy Migration ◽

Voltage Electron ◽

Reaction Rate Theory ◽

Defect Reactions

During in-situ radiation damage experiments aiming on the investigation of vacancy-migration properties interstitial-type dislocation loops are used as probes monitoring the development of the point defect concentrations. The temperature dependence of the loop-growth rate v is analyzed in terms of reaction-rate theory yielding information on the vacancy migration enthalpy. The relation between v and the point-defect production rate P provides a critical test of such a treatment since it is sensitive to the defect reactions which are dominant. If mutual recombination of vacancies and interstitials is the dominant reaction, vαP0.5 holds. If, however, annihilation of the defects at unsaturable sinks determines the concentrations, a linear relationship vαP is expected.Detailed studies in pure bcc-metals yielded vαPx with 0.7≾×≾1.0 showing that besides recombination of vacancies and interstitials annihilation at sinks plays an important role in the concentration development which has properly to be incorporated into the rate equations.

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Quantitative Model-Based Image Analysis of NuMa Distribution Links Nuclear Organization with Cell Phenotype

Microscopy and Microanalysis ◽

10.1017/s1431927600028968 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 578-579

Author(s):

David W. Knowles ◽

Sophie A. Lelièvre ◽

Carlos Ortiz de Solόrzano ◽

Stephen J. Lockett ◽

Mina J. Bissell ◽

...

Keyword(s):

Image Analysis ◽

Mammary Epithelial Cells ◽

Nuclear Organization ◽

Critical Role ◽

Quantitative Model ◽

Mammary Epithelial ◽

Cell Phenotype ◽

Proliferating Cells ◽

Mitotic Apparatus ◽

Model Based

The extracellular matrix (ECM) plays a critical role in directing cell behaviour and morphogenesis by regulating gene expression and nuclear organization. Using non-malignant (S1) human mammary epithelial cells (HMECs), it was previously shown that ECM-induced morphogenesis is accompanied by the redistribution of nuclear mitotic apparatus (NuMA) protein from a diffuse pattern in proliferating cells, to a multi-focal pattern as HMECs growth arrested and completed morphogenesis . A process taking 10 to 14 days.To further investigate the link between NuMA distribution and the growth stage of HMECs, we have investigated the distribution of NuMA in non-malignant S1 cells and their malignant, T4, counter-part using a novel model-based image analysis technique. This technique, based on a multi-scale Gaussian blur analysis (Figure 1), quantifies the size of punctate features in an image. Cells were cultured in the presence and absence of a reconstituted basement membrane (rBM) and imaged in 3D using confocal microscopy, for fluorescently labeled monoclonal antibodies to NuMA (fαNuMA) and fluorescently labeled total DNA.

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