Nauki Techniczne

Opto-Electronics Review

Zawartość

Opto-Electronics Review | 2024 | 32 | 2

Abstrakt

Concentrator photovoltaic (CPV) systems have proven the capability of competing with traditional photovoltaic (PV) systems due to their high efficiency and low area occupancy. Such CPV systems require efficient heat removal auxiliary systems, especially for medium and high optical concentration ratios. Operating a CPV system under a high optical concentration (ratio > 200 X) might require active cooling techniques, which have high operating costs and maintenance. On the other hand, heat pipes (HPs) are widely used in electronic devices for cooling purposes. This work discusses the possibility of operating a CPV system coupled with HPs as a passive cooling technique. Two different HPs with different lengths are used to compare cooling efficiency. Each HP length was tested either in a single or double configuration. Long HPs showed better heat removal compared to a traditional fin-cooling system. CVP cooling with HP systems enhanced the entire electrical output of the cell, mainly at high optical concentration ratios.
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Autorzy i Afiliacje

Mohammed Al Turkestani
1
ORCID: ORCID
Mohamed Sabry
1 2
ORCID: ORCID
Abdelrahman Lashin
1 3
ORCID: ORCID

  1. Physics Department, College of Science, Umm Al Qura University, Makkah, Kingdom of Saudi Arabia
  2. Solar Physics Lab, National Research Institute of Astronomy and Geophysics, Cairo, Egypt
  3. Physics Department, Faculty of Science, Mansoura University, Mansoura, Egypt

Abstrakt

Absorption of the below-bandgap solar radiation and direct pre-thermalizational impact of a hot carrier (HC) on the operation of a single-junction solar cell are ignored by the Shockley-Queisser theory. The detrimental effect of the HC is generally accepted only via the thermalization-caused heating of the lattice. Here, the authors demonstrate experimental evidence of the HC photocurrent induced by the below-bandgap 0.92 eV photon energy radiation in an industrial silicon solar cell. The carriers are heated both through direct free-carrier absorption and by residual photon energy remaining after the electron-hole pair generation. The polarity of the HC photocurrent opposes that of the conventional generation photocurrent, indicating that the total current across the p-n junction is contingent upon the interplay between these two currents. A model of current-voltage characteristics analysis allowing us to obtain a reasonable value of the HC temperature was also proposed. This work is remarkable in two ways: first, it contributes to an understanding of HC phenomena in photovoltaic devices, and second, it prompts discussion of the HC photocurrent as a new intrinsic loss mechanism in solar cells.
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Autorzy i Afiliacje

Ihor Zharchenko
1
Jonas Gradauskas
2
Oleksandr Masalskyi
1 2
Aleksej Rodin
1

  1. Laboratory of Electronic Processes, Center for Physical Sciences and Technology, Saulėtekio Ave. 3, LT-10257 Vilnius, Lithuania
  2. Department of Physics, Vilnius Gediminas Technical University, Saulėtekio Ave. 11, LT-10223 Vilnius, Lithuania

Abstrakt

In this paper, the authors report strain-balanced M-structures InAs/GaSb/AlSb/GaSb superlattice growth on GaSb substrates using two kinds of interfaces (IFs): GaAs-like IFs and InSb-like IFs. The in-plane compressive strain of 60-period and 100-period InAs��/GaSb/AlSb��/GaSb with different InAs (��) and AlSb (��) monolayers are investigated. The M-structures InAs/GaSb/AlSb/GaSb represent type II superlattices (T2SL) and at present are under intensive investigation. Many authors show theoretical and experimental results that such structures can be used as a barrier material for a T2SL InAs/GaSb absorber tuned for long-wave infrared detectors (8 μm–14 μm). Beside that, M-structure can also be used as an active material for short-wave infrared detectors to replace InAs/GaSb which, for this region of infrared, are a big challenge from the point of view of balancing compression stress. The study of InAs/GaSb/AlSb/GaSb superlattice with the minimal strain for GaSb substrate can be obtained by a special procedure of molecular beam epitaxy growth through special shutters sequence to form both IFs. The authors were able to achieve smaller minimal mismatches of the lattice constants compared to literature. The high-resolution X-ray diffraction measurements prove that two types of IFs are proper for balancing the strain in such structures. Additionally, the results of Raman spectroscopy, surface analyses of atomic force microscopy, and differential interference contrast microscopy are also presented. The numerical calculations presented in this paper prove that the presence of IFs significantly changes the energy gap in the case of the investigated M-structures. The theoretical results obtained for one of the investigated structures, for a specially designed structure reveal an extra energy level inside the energy gap. Moreover, photoluminescence results obtained for this structure prove the good quality of the synthesized M-structures, as well as are in a good agreement with theoretical calculations.
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Autorzy i Afiliacje

Michał Marchewka
1
ORCID: ORCID
Dawid Jarosz
1 2
ORCID: ORCID
Marta Ruszała
1
ORCID: ORCID
Anna Juś
1
ORCID: ORCID
Piotr Krzemiński
1
ORCID: ORCID
Ewa Bobko
1
ORCID: ORCID
Małgorzata Trzyna-Sowa
1
ORCID: ORCID
Renata Wojnarowska-Nowak
1
ORCID: ORCID
Paweł Śliż
1
ORCID: ORCID
Michał Rygała
3
ORCID: ORCID
Marcin Motyka
3
ORCID: ORCID

  1. Center for Microelectronics and Nanotechnology, Institute of Materials Engineering, University of Rzeszów,al. Rejtana 16, 35-959 Rzeszów, Poland
  2. International Research Centre MagTop, Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668 Warsaw, Poland
  3. Laboratory for Optical Spectroscopy of Nanostructures, Department of Experimental Physics, Faculty of Fundamental Problems ofTechnology, Wrocław University of Science and Technology, ul. Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland

Abstrakt

The goals of this work are to design and develop a technology for fabrication and study of multifunctional properties of core/shell nanoparticles (NPs) as magnetic/luminescent markers. The new hybrid core/shell Fe3O4/Gd2O3:1% Er3+, 18% Yb3+, 2.5% Mg2+, x% Nd3+ NPs doped with different concentrations of neodymium ions, where x = 0%, 0.5%, 0.75%, 1%, 2%, 4%, were synthesized by the co-precipitation method. The NPs were characterised using XRD, TEM, SEM, EDX, confocal microscopy and photoluminescence. Fe3O4 (core) consists of several 13 nm NPs. The core/shell NPs have sizes from 220 nm to 641 nm. In this latter case, the shell thicknesses were 72, 80, and 121 nm. The upconversion efficiency properties and magnetic properties of the hybrid NPs were investigated. In the core/shell NPs, the addition of Nd3+ quenches the luminescence. The magnetic response of core/shell samples is rather paramagnetic and does not differ significantly from that registered for the shell material alone. For Gd2O3:1% Er3+, 18% Yb3+ and Fe3O4/Gd2O3:1% Er3+, 18% Yb3+, 2.5% Mg2+, 0.5% Nd3+, at 300 K, the values of the magnetization registered at ~ 40 kOe are similar and equal to ~ 5.3 emu·g−1. The survivability of the HeLa tumor cells with the presence of the core/shell NPs was investigated for 24 h. The NPs are non-toxic up to a concentration of 1000 µg·ml−1 and penetrate cells in the process of endocytosis which has been confirmed by confocal microscope studies.
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Autorzy i Afiliacje

Izabela Kamińska
1
ORCID: ORCID
Kamil Sobczak
2
Yaroslav Zhydachevskyy
1
ORCID: ORCID
Tomasz Wojciechowski
1 3
ORCID: ORCID
Roman Minikayev 
1
ORCID: ORCID
Bożena Sikora-Dobrowolska
1
ORCID: ORCID
Sabina Lewińska
1
ORCID: ORCID
Michał Chojnacki
1 3
ORCID: ORCID
Krzysztof Fronc
1 3
ORCID: ORCID

  1. Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, Warsaw 02-668, Poland
  2. Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, ul. Żwirki i Wigury 101, Warsaw 02-089, Poland
  3. International Research Centre MagTop, al. Lotników 32/46, Warsaw 02-668, Poland

Abstrakt

The main goal of the article is to present the concept of using a simulation environment when designing an advanced fibre-optic seismometer (FOS) using a field-programmable gate array (FPGA) computing system. The first part of the article presents the advanced requirements regarding the FOS principle of operation, as well as the measurement method using a closed-loop operation. The closed-loop control algorithm is developed using the high-level language C++ and then it is synthesised into an FPGA. The following part of the article describes the simulation environment developed to test the operation of the control algorithm. The environment includes a model of components of the measurement system, delays, and distortions in the signal processing path, and some of the measurement system surroundings. The article ends with a comparison of simulation data with measurements. The obtained results are consistent and prove correctness of the methodology adopted by the authors.
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Autorzy i Afiliacje

Marek Kamiński
1
ORCID: ORCID
Wojciech Tylman
1
ORCID: ORCID
Grzegorz Jabłoński
1
ORCID: ORCID
Rafał Kotas
1
ORCID: ORCID
Piotr Amrozik
1
ORCID: ORCID
Bartosz Sakowicz
1
ORCID: ORCID
Leszek R. Jaroszewicz
2 3
ORCID: ORCID

  1. Department of Microelectronics and Computer Science, Lodz University of Technology, ul. Wolczanska 221, 93-005 Lodz, Poland
  2. Institute of Applied Physics, Military University of Technology, ul. gen. Sylwestra Kaliskiego 2, 00-908 Warszawa, Poland
  3. Elproma Elektronika Sp. z o.o., ul. Duńska 2A, 05-152 Czosnów, Poland