Applied sciences

Opto-Electronics Review

Content

Opto-Electronics Review | 2016 | vol. 24 | No 1 |

Download PDF Download RIS Download Bibtex

Abstract

In recent years, GaN-based light-emitting diode (LED) has been widely used in various applications, such as RGB lighting system, full-colour display and visible-light communication. However, the internal quantum efficiency (IQE) of green LEDs is significantly lower than that of other visible spectrum LED. This phenomenon is called “green gap”. This paper briefly describes the physical mechanism of the low IQE for InGaN/GaN multiple quantum well (MQW) green LED at first. The IQE of green LED is limited by the defects and the internal electric field in MQW. Subsequently, we discuss the recent progress in improving the IQE of green LED in detail. These strategies can be divided into two categories. Some of these methods were proposed to enhance crystal quality of InGaN/GaN MQW with high In composition and low density of defects by modifying the growth conditions. Other methods focused on increasing electron-hole wave function overlap by eliminating the polarization effect.

Go to article

Authors and Affiliations

Q. Zhou
M. Xu
H. Wang
Download PDF Download RIS Download Bibtex

Abstract

In this paper an analysis of the surface properties of (Ti,Pd,Eu)Ox thin films prepared by magnetron sputtering has been described. In particular, the results of composition and structure investigations were studied in relation to the surface state and optical properties. It was found that (Ti,Pd,Eu)Ox film was nanocrystalline and had a rutile structure. The average crystallites size was equal to 7.8 nm. Films were homogeneous and had densely packed grains. Investigation of the surface properties by XPS showed that titanium was present at 4+ state (in the TiO2form), palladium occurred as PdO2(also at 4+ state), while europium was in Eu2O3form (at 3+ state). In comparison with the unmodiffied TiO2, the coating with Pd and Eu additives had a rather high transparency (approx. 47%) in the visible light range, its optical absorption edge was shifted towards into the longer wavelengths (from 345 nm to 452 nm), and the width of optical energy gap Egopt was nearly twice lower (1.82 eV). Besides, the resistivity of (Ti,Pd,Eu)Ox at room temperature was 1×103 Wcm. In the case of the film as-deposited on Si substrate (p-type) the generation of photocurrent as a response to light beam excitation (λexc = 527 nm) was observed.

Go to article

Authors and Affiliations

D. Wojcieszak
D. Kaczmarek
J. Domaradzki
Download PDF Download RIS Download Bibtex

Abstract

The article presents an overview of polymeric materials for flexible substrates in photovoltaic (PV) structures that could be used as power supply in the personal electronic systems. Four types of polymers have been elected for testing. The first two are the most specialized and heat resistant polyimide films. The third material is transparent polyethylene terephthalate film from the group of polyesters which was proposed as a cheap and commercially available substrate for the technology of photovoltaic cells in a superstrate configuration. The last selected polymeric material is a polysiloxane, which meets the criteria of high elasticity, is temperature resistant and it is also characterized by relatively high transparency in the visible light range. For themost promising of these materials additional studies were performed in order to select those of them which represent the best optical, mechanical and temperature parameters according to their usage for flexible substrates in solar cells.

Go to article

Authors and Affiliations

K. Znajdek
Maciej Sibiński
ORCID: ORCID
A. Strąkowska
Z. Lisik
Download PDF Download RIS Download Bibtex

Abstract

Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

Go to article

Authors and Affiliations

M. Hosseinnezhad
S. Rouhani
Download PDF Download RIS Download Bibtex

Abstract

Non-intentionally doped GaSb epilayers were grown by molecular beam epitaxy (MBE) on highly mismatched semi-insulating GaAs substrate (001) with 2 offcut towards (110). The effects of substrate temperature and the Sb/Ga flux ratio on the crystalline quality, surface morphology and electrical properties were investigated by Nomarski optical microscopy, X-ray diffraction (XRD) and Hall measurements, respectively. Besides, differential Hall was used to investigate the hole concentration behaviour along the GaSb epilayer. It is found that the crystal quality, electrical properties and surface morphology are markedly dependent on the growth temperature and the group V/III flux ratio. Under the optimized parameters, we demonstrate a low hole concentration at very low growth temperature. Unfortunately, the layers grown at low temperature are characterized by wide FWHM and low Hall mobility.

Go to article

Authors and Affiliations

D. Benyahia
Łukasz Kubiszyn
Krystian Michalczewski
ORCID: ORCID
A. Kębłowski
Piotr Martyniuk
ORCID: ORCID
J. Piotrowski
A. Rogalski

Instructions for authors

Additional info

Opto-Electronics Review was established in 1992 for the publication of scientific papers concerning optoelectronics and photonics materials, system and signal processing. This journal covers the whole field of theory, experimental verification, techniques and instrumentation and brings together, within one journal, contributions from a wide range of disciplines. Papers covering novel topics extending the frontiers in optoelectronics and photonics are very encouraged. The main goal of this magazine is promotion of papers presented by European scientific teams, especially those submitted by important team from Central and Eastern Europe. However, contributions from other parts of the world are by no means excluded.

Articles are published in OPELRE in the following categories:

-invited reviews presenting the current state of the knowledge,

-specialized topics at the forefront of optoelectronics and photonics and their applications,

-refereed research contributions reporting on original scientific or technological achievements,

-conference papers printed in normal issues as invited or contributed papers.

Authors of review papers are encouraged to write articles of relevance to a wide readership including both those established in this field of research and non-specialists working in related areas. Papers considered as “letters” are not published in OPELRE.

Opto-Electronics Review is published quarterly as a journal of the Association of Polish Electrical Engineers (SEP) and Polish Academy of Sciences (PAS) in cooperation with the Military University of Technology and under the auspices of the Polish Optoelectronics Committee of SEP.

Abstracting and Indexing:

Arianta

BazTech

EBSCO relevant databases

EBSCO Discovery Service

SCOPUS relevant databases

ProQuest relevant databases

Clarivate Analytics relevant databases

WangFang

additionally:

ProQuesta (Ex Libris, Ulrich, Summon)

Google Scholar

Policies and ethics:

The editors of the journal place particular emphasis on compliance with the following principles:

Ethical policy of Opto-Electronics Review

The ethical policy of Opto-Electronics Review follows the European Code of Conduct for Research Integrity and is also guided by the core practices and policies outlined by the Committee on Publication Ethics (COPE).

Authors must be honest in presenting their results and conclusions of their research. Research misconduct is harmful for knowledge.

Research results

Fabrication, falsification, or selective reporting of data with the intent to mislead or deceive is unethical, as is the theft of data or research results from others. The results of research should be recorded and maintained to allow for analysis and review. Following publication, the data should be retained for a reasonable period and made available upon request. Exceptions may be appropriate in certain circumstances to preserve privacy, to assure patent protection, or for similar reasons.

Authorship

All those who have made a significant contribution should be given chance to be cited as authors. Other individuals who have contributed to the work should be acknowledged. Articles should include a full list of the current institutional affiliations of all authors, both academic and corporate.

Competing interests

All authors, referees and editors must declare any conflicting or competing interests relating to a given article. Competing interests through their potential influence on behavior or content or perception may undermine the objectivity, integrity, or perceived value of publication.

Peer Review

We are committed to prompt evaluation and publication of fully accepted papers in Opto-Electronics Review’s publications. To maintain a high-quality publication, all submissions undergo a rigorous review process.

Characteristics of the peer review process are as follows:

• Simultaneous submissions of the same manuscript to different journals will not be tolerated.

• Manuscripts with contents outside the scope will not be considered for review.

• Opto-Electronics Review is a single-blind review journal.

• Papers will be refereed by at least 2 experts as suggested by the editorial board.

• In addition, Editors will have the option of seeking additional reviews when needed. Authors will be informed when Editors decide further review is required.

• All publication decisions are made by the journal’s Editor-in-Chief based on the referees’ reports. Authors of papers that are not accepted are notified promptly.

• All submitted manuscripts are treated as confidential documents. We expect reviewers to treat manuscripts as confidential material.

• Editors and reviewers involved in the review process should disclose conflicts of interest resulting from direct competitive, collaborative, or other relationships with any of the authors, and remove oneself from cases in which such conflicts preclude an objective evaluation. Privileged information or ideas that are obtained through peer review must not be used for competitive gain.

• A reviewer should be alert to potential ethical issues in the paper and should bring these to the attention of the editor, including any substantial similarity or overlap between the manuscript under consideration and any other published paper of which the reviewer has personal knowledge. Any statement, observation, derivation, or argument that had been previously reported should be accompanied by the relevant citation.

• Personal criticism is inappropriate.

Plagiarism

Reproducing text from other papers without properly crediting the source (plagiarism) or producing many papers with almost the same content by the same authors (self-plagiarism) is not acceptable. Submitting the same results to more than one journal concurrently is unethical. Exceptions are the review articles. Authors may not present results obtained by others as if they were their own. Authors should acknowledge the work of others used in their research and cite publications that have influenced the direction and course of their study.

Plagiarism is not tolerated. All manuscripts submitted to Opto-Electronics Review will be checked for plagiarism (copying text or results from other sources) and self-plagiarism (duplicating substantial parts of authors’ own published work without giving the appropriate references) using the CrossCheck database (iThenticate plagiarism checker).

Duplicate submission

Simultaneous submissions of the same manuscript to different journals will not be tolerated. The submitted article will be removed without consideration.

Corrections and retractions

All authors have an obligation to inform and cooperate with journal editors to provide prompt retractions or correction of errors in published works.

• The journal will issue retractions if:

• There is clear evidence that the findings are unreliable, either as a result of misconduct (e.g., data fabrication or honest error - miscalculation or experimental error);

• The findings have previously been published elsewhere without proper cross-referencing, permission or justification (i.e., cases of redundant publication);

• It constitutes plagiarism;

• It reports unethical research.

• The journal will issue errata, if:

• A small portion of an otherwise reliable publication proves to be misleading (especially because of honest error);

• The author list is incorrect.

Other forms of misconduct include failure to meet clear ethical and legal requirements such as misrepresentation of interests, breach of confidentiality, lack of informed consent and abuse of research subjects or materials. Misconduct also includes improper dealing with infringements, such as attempts to cover up misconduct and reprisals on whistleblowers.

The primary responsibility for handling research misconduct is in the hands of those who employ the researchers. If a possible misconduct is brought to our attention, we will seek advice from the referees and the Editorial Board. If there is the evidence, we will resolve the matter by appropriate corrections in the printed and online journal; by refusing to consider an author's future work and by contacting affected authors and editors of other journals.

Human and Animal Rights

If the work involves the use of human subjects, the author should ensure that the work described has been carried out in accordance with The Code of Ethics of the World Medical Association (Declaration of Helsinki) for experiments involving humans; Uniform Requirements for manuscripts submitted to Biomedical journals. Authors should include a statement in the manuscript that informed consent was obtained for experimentation with human subjects. The privacy rights of human subjects must always be observed.

All animal experiments should comply with the ARRIVE guidelines and should be carried out in accordance with the EU Directive 2010/63/EU for animal experiments, and the authors should clearly indicate in the manuscript that such guidelines have been followed.

This page uses 'cookies'. Learn more