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Electron transport in electrically biased inverse parabolic double-barrier structure

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Chinese Physics B 2016年第5期25卷 326-332页

作者： M Bati s sakiroglu i sokmen Physics Department Faculty of Science Dokuz Eylül University Physics Department Graduate School of Natural and Applied Sciences Dokuz Eylül University Physics Department Faculty of Arts and Sciences Recep Tayyip Erdogan University

A theoretical study of resonant tunneling is carried out for an inverse parabolic double-barrier structure subjected to an external electric field. Tunneling transmission coefficient and density of states are analyzed by using the non-equilibrium Green＇s function approach based on the finite difference method. it is found that the resonant peak of the transmission coefficient, being unity for a symmetrical case, reduces under the applied electric field and depends strongly on the variation of the structure parameters.

关键词： inverse parabolic double-barrier structure resonant tunneling non-equilibrium Green's function electric field

spin texturing in quantum wires with Rashba and Dresselhaus spin-orbit interactions and in-plane magnetic field

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Chinese Physics B 2016年第1期25卷 750-756页

作者： B Gisi s sakiroglu i sokmen Physics Department Graduate School of Natural and Applied SciencesDokuz Eyll Universityizmir 35390Turkey Physics Department Faculty of ScienceDokuz Eyll Universityizmir 35390Turkey

in this work, we investigate the effects of interplay of spin-orbit interaction and in-plane magnetic fields on the electronic structure and spin texturing of parabolically confined quantum wire. Numerical results reveal that the competing effects between Rashba and Dresselhaus spin--orbit interactions and the external magnetic field lead to a complicated energy spectrum. we find that the spin texturing owing to the coupling between subbands can be modified by the strength of spin- orbit couplings as well as the magnitude and the orientation angle of the external magnetic field.

关键词： spin-orbit coupling quantum wire spin texture

synthesis and characterization of bulk composite Fe-si-B alloys with small concentration of Nb and Mo

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Acta Metallurgica sinica(English Letters) 2010年第6期23卷 401-408页

作者： s.Bez i.Betancourt i.A.Figueroa institute for Materials Research National Autonomous University of Mexico (UNAM)

The preparation and some mechanical, thermal and magnetic properties of the as cast bulk composite ***4 （M=Nb, Mo） alloys obtained by suction casting are presented and discussed. The microstructrural results showed the existence of a crystalline a-Fe（si） phase embedded in a glassy matrix. The values of microhardness （/iv） and yield strength （ay） for the Nb-containing alloy are exceptionally high, i.e. （12.65~0.3） GPa and （4.22~0.10） GPa, respectively. The saturation polarization values are found to be as high as 1.24 T for both composite ~11oys. it is thought that the interplay between the secondary crystalline phases and amorphous matrix could be responsible for the mechanical and magnetic behaviour of these alloys.

关键词： Bulk composite alloys Magnetic properties Mechanical proper- ties Thermal stability and suction casting

Numerical investigation and potential tunability scheme on e^+e^- and π^+π^- stimulated pair creation from vacuum using high intensity laser beams

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High Power Laser science and Engineering 2016年第4期4卷 1-7页

作者： i.Ploumistakis s.D.Moustaizis i.Tsohantjis Technical University of Crete Laboratory of Matter Structure and Laser Physics National and Kapodistrian University of Athens Faculty of PhysicsDepartment of Nuclear and Particle Physics

Numerical estimates for electrons and mesons particle–antiparticle creation from vacuum in the presence of strong electromagnetic fields are derived, using the complete probability density relation of Popov's imaginary time method(Popov, JETP Lett. 13, 185(1971); sov. Phys. JETP 34, 709(1972); sov. Phys. JETP 35, 659(1972); Popov and Marinov, sov. J. Nucl. Phys. 16, 449(1973); JETP Lett. 18, 255(1974); sov. J. Nucl. Phys. 19, 584(1974));(Popov,Phys. Let. A 298, 83(2002)), and within the framework of an experimental setup like the E144(Burke et al., Phys. ***. 79, 1626(1997)). The existence of crossing point among pair creation efficiency curves of different photon energies and the role of odd/even multiphoton orders in the production rates are discussed. Finally a kind of tunability process between the two creation processes is discussed.

关键词： high intensity lasers multiphoton processes pair production

Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： s.w.wi Y.s.Lee Department of Physics and integrative institute of Basic sciences Soongsil UniversitySeoul06978Republic of Korea

we investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence sensitizer Rare earths

Biomimetic amelioration of zirconium nanoparticles on a rigid substrate over viscous slime--a physiological approach

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1563-1576页

作者： s.i.ABDELsALAM A.Z.ZAHER instituto de Ciencias MatemHu DiNGticas iCMAT Madrid 28049Spain Basic science Faculty of EngineeringThe British University in EgyptAl-Shorouk CityCairo 11837Egypt Basic science Department Faculty of EngineeringShubra-Benha UniversityCairo 11884Egypt

in this article,an investigation is conducted to study the precise role of zirconium nanoparticles that exist in a slime-like fluid subject to specific *** gliding is a technique of mobility used by bacteria that lack motility components,bacteria travel on their own strength in gliding locomotion by secreting a layer of slime on the substrate.A model of an undulating sheet over a layer of slime of a Rabinowitsch fluid is investigated as a potential model of bacteria’s gliding *** the aid of long wavelength approximation,the equations governing the circulation of slime underneath the cells are established and analytically *** effects of pseudoplasticity,dilatation and non-Newtonian parameter on the behavior of zirconium concentration,speed of microorganism(bacteria),streamline patterns,and pressure rise for non-Newtonian and Newtonian fluids are *** power required for propulsion is also *** interpretation for the pertinent variables has been graphically discussed against the parameters under *** is found that with the increase in the concentration of zirconium nanoparticles,the bacterial flow is accelerated and attains its maximum near the rigid substrate wall while an opposite behavior is noticed in the rest region.

关键词： zirconium nanoparticle gliding bacterium Grashof heat transfer glider's speed Rabinowitsch fluid

Quantization of the O（N） Nonlinear sigma Model

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Communications in Theoretical Physics 2002年第5期37卷 567-570页

作者： s.i.Muslih DepartmentofPhysics Al－AzharUniversityGazaPalestine

The Hamilton-Jacobi method of quantizing singular systems is discussed. The equations of motion areobtained as total differential equations in many variables. it is shown that if the system is integrable, one can obtain thecanonical phase space coordinates and set of canonical Hamilton-Jacobi partial differential equations without any needto introduce unphysical auxiliary fields. As an example we quantize the O(2) nonlinear sigma model using two differentapproaches: the functional schrodinger method to obtain the wave functionals for the ground and the exited state andthen we quantize the same model using the canonical path integral quantization as an integration over the canonicalphase-space coordinates.

关键词：量子力学 O(N)非线性sigma模型量子化

Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： william J.Flerlage Mark L.Dell’Acqua Brian M.Cox Fereshteh s.Nugent Uniformed services University of the Health sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

Dual-wavelength Holmium-Doped Fiber Laser Pumped by Thulium-Ytterbium Co-Doped Fiber Laser

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Chinese Physics Letters 2016年第5期33卷 39-42页

作者： A.A.Latiff A.Dhar s.w.Harun i.M.Babar s.Das M.C.Paul H.Ahmad Photonics Research Center University of Malaya Faculty of Electronics & Computer Engineering Universiti Teknikal Malaysia Melaka CsiR-Central Glass and Ceramic Research institute Department of Electrical Engineering University of Malaya

we present an all-fiber dual-wavelength holmium-doped veloped holmium-doped fiber （HDF） as a gain medium fiber laser operating in 2 #m region using a newly de- The proposed fiber laser is constructed by using a hybrid gain medium, i.e., a thulium ytterbium co-doped fiber （TYDF） and an HDF in conjunction with a simple half-opened linear cavity, which is formed by a broadband mirror and an output coupler reflector. without the HDF, the TYDF laser operates at wavelengths of 1991 and 1999nm with a signal-to-noise ratio of more than 34dB and the slope efficiency of 26.16 %. with the HDF, dual-wavelength output lines are obtained at 2075 and 2083nm with signal-to-noise ratios of more than difference between the two peaks of less than 1 dB at 17dB, 3dB bandwidth of less than 0.2nm and the power the TYDF laser pump power of 320row.

关键词： by in is as nm of Dual-wavelength Holmium-Doped Fiber Laser Pumped by Thulium-Ytterbium Co-Doped Fiber Laser HDF