A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.
{"title":"Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonators","authors":"Yibo Tang, Longhui He, Jianming Xu, Hailang He, Yuhan Li, Anfeng Liu","doi":"10.1051/epjap/2020200145","DOIUrl":"https://doi.org/10.1051/epjap/2020200145","url":null,"abstract":"A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82483297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.1051/epjap/2020200101
I. Shimizu, Yoshinori Saikawa, K. Uno, H. Kano, S. Shimizu
A novel real image in-line laser holography has enabled a tuneable image contrast, edge sharpness, and visualization of sub-wavelength structures, using a simple pair of filters and large-diameter lenses that can incorporate higher-order scattered beams. Demonstrated also are the accuracy in object sizing and the ease of imaging along the focal depth, based on a single-shot imaging via holographic principle. In addition, the use of broad, collimated laser beam for irradiation has led to a wider field of view, making it particularly useful for an extensive monitoring of, and sweeping search for, cells and microbial colonies and for the real-time imaging of cancer-cell dynamics.
{"title":"Contrast-tuneable microscopy for single-shot real-time imaging","authors":"I. Shimizu, Yoshinori Saikawa, K. Uno, H. Kano, S. Shimizu","doi":"10.1051/epjap/2020200101","DOIUrl":"https://doi.org/10.1051/epjap/2020200101","url":null,"abstract":"A novel real image in-line laser holography has enabled a tuneable image contrast, edge sharpness, and visualization of sub-wavelength structures, using a simple pair of filters and large-diameter lenses that can incorporate higher-order scattered beams. Demonstrated also are the accuracy in object sizing and the ease of imaging along the focal depth, based on a single-shot imaging via holographic principle. In addition, the use of broad, collimated laser beam for irradiation has led to a wider field of view, making it particularly useful for an extensive monitoring of, and sweeping search for, cells and microbial colonies and for the real-time imaging of cancer-cell dynamics.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78222134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.1051/epjap/2020200021
E. Korzeniewska, J. Sekulska-Nalewajko, J. Gocławski, T. Dróżdż, P. Kiełbasa
The pulsed electric field (PEF) is one of the non-thermal methods used in the food industry for prolonging food preservation or obtaining better quality of end products. The structure of fruit and vegetable tissues subjected to PEF treatment changes under the influence of short-term high voltage electrical impulses. In this process, the hydrophilic spaces in the cell membranes occur. The authors present the results of the assessment of structural changes in fruit subjected to PEF, using the textural analysis of sub-peel layers. The images were obtained by optical coherence tomography (OCT) at an infrared wavelength of 1300 nm. The OCT cross-sections revealed the zone of strong infrared light reflection from internal structures indicating the loss of parenchymatic tissue integrity. The intensity of these changes depended on fruit type and used parameters of PEF. It was shown that the increasing intensity of the electric field affecting the tissue structure of raspberry or grape fruit generally increases the entropy, standard deviation and the mean of their OCT images. Changes in these feature values are usually not proportional to the field strength (0, 3.3, 5 kV/cm) and depend on the depth below the fruit surface. The raspberry fruit is more sensitive to PEF because at the strength of 5 kV/cm the corresponding features of grape fruit behave similarly with 10 times more field pulses. The OCT method can be used to assess noninvasively the suitability of fruit for further stages of processing, e.g. in PEF assisted pressing of fruit juice.
{"title":"Analysis of changes in fruit tissue after the pulsed electric field treatment using optical coherence tomography","authors":"E. Korzeniewska, J. Sekulska-Nalewajko, J. Gocławski, T. Dróżdż, P. Kiełbasa","doi":"10.1051/epjap/2020200021","DOIUrl":"https://doi.org/10.1051/epjap/2020200021","url":null,"abstract":"The pulsed electric field (PEF) is one of the non-thermal methods used in the food industry for prolonging food preservation or obtaining better quality of end products. The structure of fruit and vegetable tissues subjected to PEF treatment changes under the influence of short-term high voltage electrical impulses. In this process, the hydrophilic spaces in the cell membranes occur. The authors present the results of the assessment of structural changes in fruit subjected to PEF, using the textural analysis of sub-peel layers. The images were obtained by optical coherence tomography (OCT) at an infrared wavelength of 1300 nm. The OCT cross-sections revealed the zone of strong infrared light reflection from internal structures indicating the loss of parenchymatic tissue integrity. The intensity of these changes depended on fruit type and used parameters of PEF. It was shown that the increasing intensity of the electric field affecting the tissue structure of raspberry or grape fruit generally increases the entropy, standard deviation and the mean of their OCT images. Changes in these feature values are usually not proportional to the field strength (0, 3.3, 5 kV/cm) and depend on the depth below the fruit surface. The raspberry fruit is more sensitive to PEF because at the strength of 5 kV/cm the corresponding features of grape fruit behave similarly with 10 times more field pulses. The OCT method can be used to assess noninvasively the suitability of fruit for further stages of processing, e.g. in PEF assisted pressing of fruit juice.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80726002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.1051/epjap/2020200185
F. Eddiai, M. Dardouri, A. Hassani, M. Badawi, K. Sbiaai, A. Hassnaoui
In this work, molecular dynamics simulations have been used to simulate the behavior of tetramer clusters behavior in Pt4 /Cu (110) and Au4 /Ag (110) systems, in the temperature range 300-600 K. All activation barriers and formation energies related to different tetramer shapes (4S, 4L, 4T, 4N and 4l) have been calculated by embedded atom method (EAM) at static regime (0 K). From an energetical point of view, the adatoms tend to diffuse via simple jumps and exchange mechanisms leading to a transition between all forms during tetramer diffusion. Statistical analysis after molecular dynamics simulations confirms that the linear 4l shape is more stable and needs high energy to be disintegrated in both systems. The lifetime study of each shape for different temperatures (from 300 K to 600 K) proves that the 4 l form is more stiff, which is in a good agreement with the formation energy predictions.
{"title":"Structure, stability, and surface diffusion of clusters: Pt4/Cu (110) AND Au4/Ag (110) surface by molecular dynamics","authors":"F. Eddiai, M. Dardouri, A. Hassani, M. Badawi, K. Sbiaai, A. Hassnaoui","doi":"10.1051/epjap/2020200185","DOIUrl":"https://doi.org/10.1051/epjap/2020200185","url":null,"abstract":"In this work, molecular dynamics simulations have been used to simulate the behavior of tetramer clusters behavior in Pt4 /Cu (110) and Au4 /Ag (110) systems, in the temperature range 300-600 K. All activation barriers and formation energies related to different tetramer shapes (4S, 4L, 4T, 4N and 4l) have been calculated by embedded atom method (EAM) at static regime (0 K). From an energetical point of view, the adatoms tend to diffuse via simple jumps and exchange mechanisms leading to a transition between all forms during tetramer diffusion. Statistical analysis after molecular dynamics simulations confirms that the linear 4l shape is more stable and needs high energy to be disintegrated in both systems. The lifetime study of each shape for different temperatures (from 300 K to 600 K) proves that the 4 l form is more stiff, which is in a good agreement with the formation energy predictions.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84146748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.1051/epjap/2020200158
N. Chakhchaoui, R. Farhan, Meriem Boutaldat, M. Rouway, A. Eddiai, M. Meddad, A. Hajjaji, O. Cherkaoui, Y. Boughaleb, L. Langenhove
Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β -phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2 CH3 )4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β -phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β -phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β -phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β -phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.
{"title":"Piezoelectric β-polymorph formation of new textiles by surface modification with coating process based on interfacial interaction on the conformational variation of poly (vinylidene fluoride) (PVDF) chains","authors":"N. Chakhchaoui, R. Farhan, Meriem Boutaldat, M. Rouway, A. Eddiai, M. Meddad, A. Hajjaji, O. Cherkaoui, Y. Boughaleb, L. Langenhove","doi":"10.1051/epjap/2020200158","DOIUrl":"https://doi.org/10.1051/epjap/2020200158","url":null,"abstract":"Novel textiles have received a lot of attention from researchers in the last decade due to some of their unique features. The introduction of intelligent materials into textile structures offers an opportunity to develop multifunctional textiles, such as sensing, reacting, conducting electricity and performing energy conversion operations. In this research work nanocomposite-based highly piezoelectric and electroactive β -phase new textile has been developed using the pad-dry-cure method. The deposition of poly (vinylidene fluoride) (PVDF) − carbon nanofillers (CNF) − tetraethyl orthosilicate (TEOS), Si(OCH2 CH3 )4 was acquired on a treated textile substrate using coating technique followed by evaporation to transform the passive (non-functional) textile into a dynamic textile with an enhanced piezoelectric β -phase. The aim of the study is the investigation of the impact the coating of textile via piezoelectric nanocomposites based PVDF-CNF (by optimizing piezoelectric crystalline phase). The chemical composition of CT/PVDF-CNC-TEOS textile was detected by qualitative elemental analysis (SEM/EDX). The added of 0.5% of CNF during the process provides material textiles with a piezoelectric β -phase of up to 50% has been measured by FTIR experiments. These results indicated that CNF has high efficiency in transforming the phase α introduced in the unloaded PVDF, to the β -phase in the case of nanocomposites. Consequently, this fabricated new textile exhibits glorious piezoelectric β -phase even with relatively low coating content of PVDF-CNF-TEOS. The study demonstrates that the pad-dry-cure method can potentially be used for the development of piezoelectric nanocomposite-coated wearable new textiles for sensors and energy harvesting applications. We believe that our study may inspire the research area for future advanced applications.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90474033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-01DOI: 10.1051/epjap/2020200107
M. Mrad, A. Tarhini, P. Bourgeois, V. Giordano
The Cryogenic Sapphire Oscillator (CSO) is currently the best available technology that can provide a relative frequency stability better than 10−15 with integration times between 1 s and 10,000 s. But, the CSO remains a complex instrument that requires multiple loop controls to achieve the best frequency stability. The possibility to use the sapphire resonator in a self-sustained MASER oscillator presents an elegant alternative to the CSO. Here, sustaining the amplification is achieved through the interaction between a high-Q factor whispering gallery mode and the paramagnetic Fe3+ ions, which are present in small concentration in the sapphire crystal. The Fe3+ ion exhibits three energy states enabling to realize a self-sustaining solid-state maser. Although, this principle has been already experimentally demonstrated few years ago, its development as a truly usable ultra-stable source has not yet been completed, mainly due to the lack of control of the complex physical phenomena involved. This paper complements the previous theoretical work based on the rate equations model. Here we derive the full quantum equations describing the evolution of the Fe3+ ions inside the sapphire lattice and submitted to a pump and a maser signal. The influence of the ions concentration and spin-spin relaxation time will be pointed out.
{"title":"Physics of the sapphire whispering-gallery-mode solid-state MASER oscillator","authors":"M. Mrad, A. Tarhini, P. Bourgeois, V. Giordano","doi":"10.1051/epjap/2020200107","DOIUrl":"https://doi.org/10.1051/epjap/2020200107","url":null,"abstract":"The Cryogenic Sapphire Oscillator (CSO) is currently the best available technology that can provide a relative frequency stability better than 10−15 with integration times between 1 s and 10,000 s. But, the CSO remains a complex instrument that requires multiple loop controls to achieve the best frequency stability. The possibility to use the sapphire resonator in a self-sustained MASER oscillator presents an elegant alternative to the CSO. Here, sustaining the amplification is achieved through the interaction between a high-Q factor whispering gallery mode and the paramagnetic Fe3+ ions, which are present in small concentration in the sapphire crystal. The Fe3+ ion exhibits three energy states enabling to realize a self-sustaining solid-state maser. Although, this principle has been already experimentally demonstrated few years ago, its development as a truly usable ultra-stable source has not yet been completed, mainly due to the lack of control of the complex physical phenomena involved. This paper complements the previous theoretical work based on the rate equations model. Here we derive the full quantum equations describing the evolution of the Fe3+ ions inside the sapphire lattice and submitted to a pump and a maser signal. The influence of the ions concentration and spin-spin relaxation time will be pointed out.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89488047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-24DOI: 10.1051/epjap/2020200162
Khadija El Batal, M. Meddad, S. Benahdouga, N. Chakhchaoui, A. Eddiai, M. Mazroui
Automated systems are fault-prone. The fault diagnosis via sensor and actuator piezoelectric is very important for the stability of the vibration control system and fault-tolerant control technology. Faults in process automation frequently lead to unexpected reactivity and the closure of a controlled plant, and the effects could be damage to technical parts of the plant, employees or the ecosystem. Fault-tolerant control is the combination between diagnostics and control techniques to cleverly handle faults. It provides improved availability and minimized safety risk. This article provides an overview of recent approaches to study and analyze the structure and other fundamental characteristics of an automated system. Thus, the starting point of this study was to investigate the Fault Tolerant Control strategy of an asynchronous machine. Ultimately, the aim is to achieve a disturbance- and/or fault-tolerant control, improving the functional reliability of this system. A decision-making device based on a piezoelectric (PZT) sensor and actuator has been developed to produce an opposite displacement to the vibratory displacement. It ensures the various reconfigurations of the control, adapted to the vibration disturbance acting on the system and modifying its characteristics. This will result in vibration attenuation. Finally, the advantages of this method are analyzed, and the fault diagnosis results with the best identification effect are determined.
{"title":"Diagnostic of electromechanical system by fault-tolerant-control using piezoelectric sensors","authors":"Khadija El Batal, M. Meddad, S. Benahdouga, N. Chakhchaoui, A. Eddiai, M. Mazroui","doi":"10.1051/epjap/2020200162","DOIUrl":"https://doi.org/10.1051/epjap/2020200162","url":null,"abstract":"Automated systems are fault-prone. The fault diagnosis via sensor and actuator piezoelectric is very important for the stability of the vibration control system and fault-tolerant control technology. Faults in process automation frequently lead to unexpected reactivity and the closure of a controlled plant, and the effects could be damage to technical parts of the plant, employees or the ecosystem. Fault-tolerant control is the combination between diagnostics and control techniques to cleverly handle faults. It provides improved availability and minimized safety risk. This article provides an overview of recent approaches to study and analyze the structure and other fundamental characteristics of an automated system. Thus, the starting point of this study was to investigate the Fault Tolerant Control strategy of an asynchronous machine. Ultimately, the aim is to achieve a disturbance- and/or fault-tolerant control, improving the functional reliability of this system. A decision-making device based on a piezoelectric (PZT) sensor and actuator has been developed to produce an opposite displacement to the vibratory displacement. It ensures the various reconfigurations of the control, adapted to the vibration disturbance acting on the system and modifying its characteristics. This will result in vibration attenuation. Finally, the advantages of this method are analyzed, and the fault diagnosis results with the best identification effect are determined.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76368255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-18DOI: 10.1051/epjap/2020200186
Hicham El Azrak, A. Hassani, K. Sbiaai, A. Hasnaoui
We have studied thin film growth of NiAl on Nickel (001) substrate using molecular dynamics simulations (MD) based on the Embedded Atom Method (EAM) potential. An incidence energy of 0.06 eV at 800 K, 900 K and 1000 K was considered. After the deposition process, we have obtained a B2-NiAl structure film with different percentages; 32.6% for the temperature 1000 K, 30% for 900 K and 25% for 800 K. Our investigation has prompt us to analyze the crystalline structure. During the evolution of deposited film, we observe the formation of grains with different orientation, as well as the appearance of vacancies in Ni and Al sublattices and antisites.
本文采用基于嵌入原子法(EAM)电位的分子动力学模拟(MD)方法研究了NiAl在镍(001)衬底上的薄膜生长。考虑800k、900k和1000k入射能量为0.06 eV。经过沉积过程，我们得到了不同百分比的B2-NiAl结构薄膜;1000 K 32.6%， 900 K 30%， 800 K 25%。我们的研究促使我们分析晶体结构。在沉积膜的演化过程中，我们观察到不同取向的晶粒的形成，以及Ni和Al亚晶格和反晶格中空位的出现。
{"title":"NiAl thin film growth on Ni(001) substrate using molecular dynamics simulations","authors":"Hicham El Azrak, A. Hassani, K. Sbiaai, A. Hasnaoui","doi":"10.1051/epjap/2020200186","DOIUrl":"https://doi.org/10.1051/epjap/2020200186","url":null,"abstract":"We have studied thin film growth of NiAl on Nickel (001) substrate using molecular dynamics simulations (MD) based on the Embedded Atom Method (EAM) potential. An incidence energy of 0.06 eV at 800 K, 900 K and 1000 K was considered. After the deposition process, we have obtained a B2-NiAl structure film with different percentages; 32.6% for the temperature 1000 K, 30% for 900 K and 25% for 800 K. Our investigation has prompt us to analyze the crystalline structure. During the evolution of deposited film, we observe the formation of grains with different orientation, as well as the appearance of vacancies in Ni and Al sublattices and antisites.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85200770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-12DOI: 10.1051/epjap/2020200138
Hang Yu, Jianlin Zhou, Yuanyuan Hao, Yao Ni
Organic thin film transistors (OTFTs) based on dioctylbenzothienobenzothiophene (C8BTBT) and copper (Cu) electrodes were fabricated. For improving the electrical performance of the original devices, the different modifications were attempted to insert in three different positions including semiconductor/electrode interface, semiconductor bulk inside and semiconductor/insulator interface. In detail, 4,4′,4′′-tris[3-methylpheny(phenyl)amino] triphenylamine (m-MTDATA) was applied between C8BTBTand Cu electrodes as hole injection layer (HIL). Moreover, the fluorinated copper phthalo-cyanine (F16 CuPc) was inserted in C8BTBT/SiO2 interface to form F16 CuPc/C8BTBT heterojunction or C8BTBT bulk to form C8BTBT/F16 CuPc/C8BTBT sandwich configuration. Our experiment shows that, the sandwich structured OTFTs have a significant performance enhancement when appropriate thickness modification is chosen, comparing with original C8BTBT devices. Then, even the low work function metal Cu was applied, a normal p-type operate-mode C8BTBT-OTFT with mobility as high as 2.56 cm2 /Vs has been fabricated.
{"title":"Effective performance improvement of organic thin film transistors with multi-layer modifications","authors":"Hang Yu, Jianlin Zhou, Yuanyuan Hao, Yao Ni","doi":"10.1051/epjap/2020200138","DOIUrl":"https://doi.org/10.1051/epjap/2020200138","url":null,"abstract":"Organic thin film transistors (OTFTs) based on dioctylbenzothienobenzothiophene (C8BTBT) and copper (Cu) electrodes were fabricated. For improving the electrical performance of the original devices, the different modifications were attempted to insert in three different positions including semiconductor/electrode interface, semiconductor bulk inside and semiconductor/insulator interface. In detail, 4,4′,4′′-tris[3-methylpheny(phenyl)amino] triphenylamine (m-MTDATA) was applied between C8BTBTand Cu electrodes as hole injection layer (HIL). Moreover, the fluorinated copper phthalo-cyanine (F16 CuPc) was inserted in C8BTBT/SiO2 interface to form F16 CuPc/C8BTBT heterojunction or C8BTBT bulk to form C8BTBT/F16 CuPc/C8BTBT sandwich configuration. Our experiment shows that, the sandwich structured OTFTs have a significant performance enhancement when appropriate thickness modification is chosen, comparing with original C8BTBT devices. Then, even the low work function metal Cu was applied, a normal p-type operate-mode C8BTBT-OTFT with mobility as high as 2.56 cm2 /Vs has been fabricated.","PeriodicalId":12228,"journal":{"name":"European Physical Journal-applied Physics","volume":null,"pages":null},"PeriodicalIF":1.0,"publicationDate":"2020-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85600868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-01DOI: 10.1051/epjap/2020200146
Z. Hireche, L. Nasseri, D. Ameziani
This article presents the hydrodynamic and thermal characteristics of transfers by forced, mixed and natural convection in a room ventilated by air displacement. The main objective is to study the effect of a porous partition on the heat transfer and therefore the thermal comfort in the room. The fluid flow future in the cavity and the heat transfer rate on the active wall have been analyzed for different permeabilities: 10−6 ≤ Da ≤ 10. The other control parameters are obviously, the Rayleigh number and the Reynolds number varied in the rows: 10 ≤ Ra ≤ 106 and 50 ≤ Re ≤ 500 respectively. The transfer equations write were solved by the Lattice Boltzmann Multiple Relaxation Time method. For flow in porous media an additional term is added in the standard LB equations, to consider the effect of the porous media, based on the generalized model, the Brinkman-Forchheimer-extended Darcy model. The most important conclusion is that the Darcian regime start for small Darcy number Da . Spatial competition between natural convection cell and forced convection movement is observed as Ra and Re rise. The effect of Darcy number values and the height of the porous layer is barely visible with a maximum deviation less than 7% over the ranges considered. Note that the natural convection regime is never reached for low Reynolds numbers. For this Re values the cooperating natural convection only improves transfers by around 10% while, for the other Reynolds numbers the improvement in transfers due to natural and forced convections cooperation is more significant.
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