| 1. |
- Greczynski, G., et al.
(författare)
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Photoelectron spectroscopy study of the energy level alignment at polymer/electrode interfaces in light emitting devices
- 2001
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Ingår i: Current applied physics. - 1567-1739 .- 1878-1675. ; 1:1, s. 98-106
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Tidskriftsartikel (refereegranskat)abstract
- The band alignment at the interface between electroluminescent polymers and the electrodes in polymer-LEDs was studied using photoelectron spectroscopy. Chemical factors like the formation of InCl3 during conversion of precursor-PPV on ITO could be directly monitored with XPS. Films of electroluminescent polymers were studied on a range of ITO and metal electrodes with different work functions, as well as with an intermediate, electrically conducting polymer layer, using UPS. Furthermore, the study of the band alignment at polymer electrode interfaces was extended to three-layer structures: the results confirm the common assumption that the potential drop over the polymer layer in polymer LEDs is equal to the difference between the electrode work functions. © 2001 Elsevier Science B.V.
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| 2. |
- Andreasson, Måns, 1975, et al.
(författare)
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Porphyrin doping of Alq3 for electroluminescence
- 2008
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Ingår i: Current Applied Physics. - 1567-1739. ; 8, s. 163-166
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Tidskriftsartikel (refereegranskat)abstract
- Organic light emitting devices based on tris(8-hydroxyquinoline)aluminium (Alq3) doped with two fluorescent porphyrin derivatives,5,15-diphenyl-2,8,12,18-tetraethyl-3,7,13,17-tetramethylporphyrin and the corresponding zinc metalated one, were fabricated. As a consequence,the light emission changed, from standard green light from Alq3, to reddish and yellowish white respectively. The differentspectral content in the two cases indicates a possible route to a white light emitter, based on several dopants from the same family ofmolecules with different central atoms. The turn-on voltage of the devices was not increased by the doping.
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| 3. |
- Benyahia, K, et al.
(författare)
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Magneto-optical Kerr effect (MOKE) of the rare-earth silicide ErSi2 using ab-initio calculations
- 2009
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Ingår i: Current applied physics. - : Elsevier BV. - 1567-1739 .- 1878-1675. ; 9:5, s. 925-927
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Tidskriftsartikel (refereegranskat)abstract
- We present a computational method for the ab-initio study of the magneto-optical quantities using the augmented plane wave plus local orbitals (APW+lo) method. The calculations are performed within the local-density (LDA) approximation. In the present paper, the optical conductivity is the basic quantity for the evaluation of the magneto-optical Kerr effect (MOKE). Thus it is well described and calculated. Considerable work has been performed on the magneto-optical Kerr effect using experiments, however, no experimental or theoretical work has been investigated on rare-earth silicide ErSi2, in particular using ab-initio method. Our results consist a prediction. (C) 2008 Elsevier B.V. All rights reserved.
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| 4. |
- Cho, Soohyun, et al.
(författare)
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Observation of Dresselhaus type spin splitting of zinc blende structure semiconductors by circular dichroic photoemission study
- 2021
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Ingår i: Current Applied Physics. - : Elsevier BV. - 1567-1739. ; 30, s. 96-101
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Tidskriftsartikel (refereegranskat)abstract
- Material family of zinc blende structure semiconductors (ZBSSs) is important for novel technique such as spintronics. A study of the ZBSS spin-splitting structure in momentum space is essential when seeking to understand the exotic properties of the material. The Dresselhaus field predominates in the bulk, but the Rashba field plays important roles in states near the surface. Here, we used circular dichroism in angle-resolved photoemission spectroscopy (CD-ARPES) to explore the spin-splitting structure of bulk ZBSS in momentum space. The observed structure was well-explained by a Dresselhaus field attributable to the lack of inversion symmetry in ZBSS crystals. We show that CD-ARPES usefully reveals spin-splitting in momentum space. CD-ARPES combined with hard x-ray incident-beam would be useful to investigate the spin-splitting structures of the interface states in the ZBSS heterostructure.
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| 5. |
- Dittmer, Staffan, 1970, et al.
(författare)
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Electric field aligned growth of single-walled nanotubes
- 2004
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Ingår i: Current Applied Physics. - : Elsevier BV. - 1567-1739. ; 4, s. 595-598
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Tidskriftsartikel (refereegranskat)abstract
- Electric field aligned, single-walled carbon nanotubes are grown between electrodes using thermal chemical vapour deposition (CVD) of methane. The growth occurs on a thin film layered catalyst of aluminium, iron and molybdenum patterned on top of electrodes. The nanotubes bridge 10 μm sized electrode gaps and have a typical diameter of less than 2 nm as measured by Raman spectroscopy and atomic force microscopy. We present electrical transport measurements on a directly grown nanotube which shows p-type semiconducting behaviour.
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| 6. |
- Hussain, Jawad, et al.
(författare)
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Modeling and simulation of planar SOFC to study the electrochemical properties
- 2020
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Ingår i: Current applied physics. - : ELSEVIER. - 1567-1739 .- 1878-1675. ; 20:5, s. 660-672
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, modeling and simulations are carried out using COMSOL Multiphysics. A three-dimensional model is developed for a planar intermediate temperature (IT) solid oxide fuel cell (SOFC). A parametric study has been carried out to analyze the performance of SOFC. Simulations reveal some promising features and enhanced performance of SOFC. It is shown that the maximum value of power (4-3.3) kW/m(2) still remains higher with significant rise of temperature (600 degrees C-1000 degrees C), nearly 0.15 kW/m(2) is the very small loss of power per 100 degrees C rise of temperature. Results have shown that the electrolytic current density is (6700-5500) A/m(2) for peak value of power (4-3.3) kW/m(2) with increase of temperature (600 degrees C-1000 degrees C). For model validation we have plotted a comparison of average current density.
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| 7. |
- Jhang, SungHo, et al.
(författare)
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Random telegraph noise in carbon nanotubes and peapods
- 2006
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Ingår i: Current Applied Physics. - : Elsevier BV. - 1567-1739. ; 6, s. 987-991
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Tidskriftsartikel (refereegranskat)abstract
- The switching of resistance between two discrete values, known as random telegraph noise (RTN), was observed in individual single-walled carbon nanotubes (SWNTs) and C60-filled SWNTs (the so-called peapods). The RTN has been studied as a function of bias-voltage and gate-voltage as well as temperature. By analyzing the features of the RTN, we identify three different types of RTN existing in the SWNT related systems. While the RTN can be generated by the various charge traps in the vicinity of the SWNTs, the RTN for metallic SWNTs is mainly due to reversible defect motions between two metastable states, activated by inelastic scattering with ballistic electrons. On the other hand, the noise for peapods can be attributed to the motion of C60 molecules in hollow space of SWNTs.
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| 8. |
- Kibbou, M., et al.
(författare)
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Cs2InGaX6 (X=Cl, Br, or I) : Emergent Inorganic Halide Double Perovskites with enhanced optoelectronic characteristics
- 2021
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Ingår i: Current applied physics. - : Elsevier BV. - 1567-1739 .- 1878-1675. ; 21, s. 50-57
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Tidskriftsartikel (refereegranskat)abstract
- During the last decade, Inorganic Halide Double Perovskite materials have attracted widespread interest as a promising eco-friendly and non-toxic alternative to lead based hybrid halide organic–inorganic perovskites materials, with outstanding Stability, Structural and electronic properties. In this study, First-Principles density functional theory (DFT) calculations were performed on the structural, stability, electronic and optical properties of the transition metal-based double perovskites materials Cs2InGaX6 (X = Cl, Br, or I). Our results reveal that all these materials exhibit excellent thermodynamic and structural stability owing to their negative formation energies and Goldsmith's factors. It is also observed that Cs2InGaCl6, Cs2InGaBr6, and Cs2InGaI6 materials exhibit band gaps calculated by different functional (GGA-PBE and TB-mpj) in visible-range between 0.89 and 3.24 eV. Furthermore, the computed optical properties reveal strong absorption in UV, visible, and IR range with high optical conductivity and low reflectivity. These obtained results predict that the three transition metal-based double perovskites materials carries promising application in nano-electronic and optoelectronic device applications and can be considered as photovoltaic absorber materials.
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| 9. |
- Lee, Sanghoon, et al.
(författare)
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Magnetotransport properties of ferromagnetic semiconductor GaMnAs-based superlattices
- 2012
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Ingår i: Current applied physics. - : Elsevier BV. - 1567-1739 .- 1878-1675. ; 12:SUPPL. 2, s. S31-S36
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Tidskriftsartikel (refereegranskat)abstract
- Two series of GaMnAs/GaAs superlattices (SSs) comprised of ferromagnetic semiconductor GaMnAs layers and non-magnetic GaAs spacers were investigated by the electronic transport measurements with an external magnetic field applied in the plane of the sample. The two SL series consisted of specimens that were structurally the same, but the GaAs spacers layers of one series were doped by Be, while in the second series the spacers were undoped. Although in field scans taken at 4 K all SLs showed a typical anisotropic magnetoresistance (MR) behavior dominated by magnetic anisotropy, similar to that normally observed in single GaMnAs ferromagnetic layers grown on GaAs (001) substrates, some of the SLs showed signatures of interaction between the GaMnAs layers in the form of broadening of the MR hysteresis. The effect of inter-layer exchange coupling (IEC) between the GaMnAs magnetic layers became clear in the MR data taken at 30 K, where the strength of the magnetic anisotropy was reduced to the level of the inter-layer interaction. Specifically, MR measurements on two of the Be-doped SLs (BD2 and BD3) exhibited conspicuously large values of resistance at zero field, along with transitions of magnetization with negative coercive fields. The observation of these features in GaMnAs/GaAs SLs indicates the presence of spontaneous antiferromagnetic (AFM) inter-layer exchange coupling (IEC) between the GaMnAs magnetic layers. The study further revealed that the IEC in the GaMnAs multilayers strongly depended on the properties of the non-magnetic GaAs spacers, such as their thickness and the density of carriers in the layers. Importantly, these IEC effects occurred on a longer range than that expected from current theoretical studies.
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| 10. |
- Lundström, Ingemar, et al.
(författare)
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Natural nanosystems
- 2002
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Ingår i: Current applied physics. - 1567-1739 .- 1878-1675. ; 2:1, s. 17-21
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Tidskriftsartikel (refereegranskat)abstract
- A short review of our work on pigment containing cells as biosensors is given. It is pointed out that they combine several natural nanosystems, namely membrane bound receptors and their biochemical machinery, and the tubulin/actin network inside the cells for transport of submicron-sized pigment particles driven by molecular motors of 10-100 nm size.
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