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spectral Hole Burning via Kerr Nonlinearity

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Communications in Theoretical Physics 2015年第10期64卷 473-478页

作者： Anwar Ali Khan m.s.abdul jabar m.Jalaluddin Bakht Amin Bacha Iftikhar Ahmad Department of Physics University of Malakand

spectral hole burning is investigated in an optical medium in the presence of Doppler broadening and Kerr nonlinearity. The Kerr nonlinearity generates coherent hole burning in the absorption spectrum. The higher order Kerr nonlinearity enhances the typical lamb dip of the hole. Normal dispersion in the hole burning region while steep anomalous dispersion between the two hole burning regions also enhances with higher order Kerr effect. A large phase shift creates large delay or advancement in the pulse propagation while no distortion is observed in the pulse. These results provide significant steps to improve optical memory, telecom devices, preservation of information and image quality.

关键词： spectral hole burning Kerr nonlinearity Doppler br

Time gap for temporal cloak based on spectral hole burning in atomic medium

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Chinese Physics B 2016年第8期25卷 175-180页

作者： abdul jabar m s Bakht Amin Bacha Iftikhar Ahmad Department of Physics University of Malakand

We demonstrate the possibility of creating a time gap in the slow light based on spectral hole burning in a fourlevel Doppler broadened sodium atomic system. A time gap is also observed between the slow and the fast light in the hole burning region and near the burnt hole region, respectively. A cloaking time gap is attained in microseconds and no distortion is observed in the transmitted pulse. The width of the time gap is observed to vary with the inverse Doppler effect in this system. Our results may provide a way to create multiple time gaps for a temporal cloak.

关键词： temporal cloak susceptibility slow and fast light spectral holes

Computational study of inverse ferrite spinels

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Chinese Physics B 2019年第5期28卷 305-311页

作者： A EL maazouzi R masrour A jabar m Hamedoun Laboratory of materials Processes Environment and Quality Cadi Ayyad University National School of Applied Sciences Institute of Nanomaterials and Nanotechnologies

The magnetic properties of inverse ferrite Fe_(3+) Fe_(3+)Co_(2+) O^(2-)_4, Fe^(3+) Fe^(3+)Cu^(2+) O^2_(-4), Fe^(3+) Fe^(3+)Fe^(2+) O^2_(-4),and Fe^(3+) Fe^(3+)Ni^(2+) O^(2-)_4spinels have been studied using monte Carlo simulation. We have also calculated the critical and Curie Weiss temperatures from the thermal magnetizations and inverse of magnetic susceptibilities for each *** hysteresis cycles have been found for the four systems. Finally, we found the critical exponents associated with magnetization, magnetic susceptibility, and external magnetic field. Our results of critical and Curie Weiss temperatures are similar to those obtained by experiment results. The critical exponents are similar to those of known 3 D-Ising model.

关键词： inverse ferrites spinels monte Carlo simulation critical and Curie Weiss temperatures magnetic hysteresis cycles critical exponents

magnetocaloric and magnetic properties of La_2NimnO_6 double perovskite

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Chinese Physics B 2016年第8期25卷 373-378页

作者： masrour R jabar A Laboratory of materials Processes Environment and Quality Cady Ayyed University National School of Applied Sciences

The magnetic effect and the magnetocaloric effect in La_2NimnO_6（LNmO） double perovskite are studied using the monte Carlo *** magnetizations,specific heat values,and magnetic entropies are obtained for different exchange interactions and external magnetic *** adiabatic temperature is *** transition temperature is *** relative cooling power is established with a fixed value of exchange *** to the master curve behaviors for the temperature dependence of △s_m^（max） predicted for different maximum fields,in this work it is confirmed that the paramagnetic-ferromagnetic phase transition observed for our sample is of a second *** near room-temperature interaction and the superexchange interaction between Ni and mn are shown to be due to the ferromagnetism of LNmO.

关键词： oxides magnetocaloric monte Carlo simulation specific heat magnetic properties

Effects of magnetic field on photon-induced quantum transport in a single dot-cavity system

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Chinese Physics B 2016年第11期25卷 270-274页

作者： Nzar Rauf abdullah Aziz H Fatah jabar m A Fatah Physics Department College of Science University of Sulaimani science Institute University of Iceland

In this study,we show how a static magnetic field can control photon-induced electron transport through a quantum dot system coupled to a photon *** quantum dot system is connected to two electron reservoirs and exposed to an external perpendicular static magnetic *** propagation of electrons through the system is thus influenced by the static magnetic and the dynamic photon *** is observed that the photon cavity forms photon replica states controlling electron transport in the *** the photon field has more energy than the cyclotron energy,then the photon field is dominant in the electron ***,the electron transport is enhanced due to activation of photon replica *** contrast,the electron transport is suppressed in the system when the photon energy is smaller than the cyclotron energy.

关键词： photon connected reservoirs zigzag suppressed perpendicular exposed spacing Hamiltonian confinement

Intrinsic ferromagnetism in CoBr2 nanolayers:a DFT+U and monte Carlo study

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Communications in Theoretical Physics 2021年第11期73卷 165-170页

作者： A jabar R masrour G Kadim m Hamedoun A Hourmatallah N Benzakour A Rezzouk K Bouslykhane J Kharbach Laboratory of solid Physics Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco mAscIR Institute of Nanomaterials and NanotechnologiesRabatMorocco Equipe de Physique du solide Laboratoire LIPIEcole Normale SupérieureBensoudaBP 5206FèsMorocco

The intrinsic ferromagnetism of CoBr2 bulk was investigated using DFT(density functional theory)combined with the full potential linear augmented plane wave method and monte Carlo *** ground state of CoBr2 exhibits ferromagnetic behavior and a semiconductor *** used the generalized gradient approximation(GGA)and GGA+U(Hubbard correction)approximations to determinate the magnetic *** magnetic moment reached the experimental value and was in good agreement with the other theoretical *** value obtained was used as an input to a monte Carlo study to calculate the thermal magnetization and magnetic hysteresis *** behavior was observed and was found to be due to an positive exchange *** results lead us to believe that this material could be a promising spintronic material.

关键词： CoBr2 nanolayer DFT monte Carlo transition temperature magnetic hysteresis cycles

spin and Orbital magnetisms of NiFe Compound:Density Functional Theory study and monte Carlo simulation

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Chinese Physics Letters 2018年第3期35卷 58-61页

作者： R.masrour A.jabar E.K.Hlil m.Hamedoun A.Benyoussef A.Hourmatallah K.Bouslykhane A.Rezzouk N.Benzakour Laboratory of materials ProcessesEnvironment and QualityCady Ayyed UniversityNational School of Applied SciencesSail 63 46000Morocco Institut Neel CNRS et Universite Grenoble AlpesBP 166F-38042 Grenoble Cedex 9France Institute of Nanomaterials and Nanotechnologies MAScIRRabatMorocco Hassan II Academy of science and Technology RabatMorocco Equipe de Physique du solide Laboratoire LIPIEcole Normale SuperieureBP 5206BensoudaFesMorocco Laboratoire de Physique du solide Universite Sidi Mohammed Ben AbdellahFaculte des Sciences Dhar MahrazBP 1796FesMorocco

The self-consistent ab initio calculations based on the density functional theory approach using the full potential linear augmented plane wave method are performed to investigate both the electronic and magnetic properties of the NiFe compound. Polarized spin within the framework of the ferromagnetic state between magnetic ions is considered. Also, magnetic moments considered to lie along （001） axes are computed. The monte Carlo simulation is used to study the magnetic properties of NiFe. The transition temperature To, hysteresis loop, coercive field and remanent magnetization of the NiFe compound are obtained using the monte Carlo simulation.

关键词： Fe spin and Orbital magnetisms of Ni Fe Compound Ni

BVRI photometric observations,light curve solutions and orbital period analysis of BF Pav

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Research in Astronomy and Astrophysics 2021年第8期21卷 193-202页

作者： Atila Poro Fahri Alicavus Eduardo Fernández-Lajús Fatemeh Davoudi Pegahsadat mirshafieKhozani mark G.Blackford Edwin Budding Behjat Zarei Jalalabadi jabar Rahimi Farzaneh Ahangarani Farahani The International Occultation Timing Association middle East section Iran Astronomy Department of the Raderon Lab BurnabyBCCanada Canakkale Onsekiz mart University Faculty of Arts and SciencesDepartment of Physics17020CanakkaleTurkey Canakkale Onsekiz mart University Astrophysics Research Center and Ulupnar Observatory17020CanakkaleTurkey Instituto de Astrofisica de La Plata(CCT La Plata-CONICET-UNLP) La PlataArgentina Facultad de Ciencias Astronomicas y Geofisicas Universidad Nacional de La PlataPaseo del BosqueB1900FWALa PlataArgentina Variable stars south(Vss) Congarinni ObservatoryCongarinniNSW2447Australia Carter Observatory 40 Salamanca RdKelburnWellington 6012New Zealand

A new ephemeris,period change analysis and light curve modeling of the W Uma-type eclipsing binary BF Pav are presented in this *** curves of the system taken in BVRI filters from two observatories,in Australia and Argentina,were modeled using the Wilson-Devinney *** results of this analysis demonstrate that BF Pav is a contact binary system with a photometric mass ratio q=1.460 ± 0.014,a fillout factor f=12.5%,an inclination of 87.97 ± 0.45 deg and a cold spot on the secondary *** applying the distance modulus formula,the distance of BF Pav was calculated to be d=268 ± 18 pc which is in good agreement with the Gaia EDR3 *** obtain an orbital period increase at a rate of 0.142 s century-1 due to a quadratic trend in the O-C ***,an alternative sudden period jump probably occurred which could be interpreted as a rapid mass transfer from the lower mass star to its companion of about Δm=2.45 × 10-6 m⊙.Furthermore,there is an oscillatory behavior with a period of 18.3±0.3 *** BF Pav does not seem to have significant magnetic activity,this behavior could be interpreted as the light-time effect caused by an undetected third body in this *** this case,the probability for the third body to be a low mass star with m≥ 0.075 m⊙or a brown dwarf is 5.4% and 94.6% *** we assume i’=90°,a3=8.04±0.33 *** mass of the secondary component was also determined following two different methods which result close to each other.

关键词： techniques:photometric binaries:eclipsing stars:individual(BF Pav)

Realizing high thermoelectric performance via selective resonant doping in oxyselenide BiCuseO

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Nano Research 2023年第1期16卷 1679-1687页

作者： Yue-Xing Chen Wenning Qin Adil mansoor Adeel Abbas Fu Li Guang-xing Liang Ping Fan muhammad Usman muzaffar Bushra jabar Zhen-hua Ge Zhuang-hao Zheng F1 shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Faculty of materials and manufacturing Beijing University of TechnologyBeijing 100124China International Center for Quantum Design of Functional materials(ICQD) Hefei National Laboratory for Physical Sciences at Microscale(HFNL)and CAS Center for Excellence in Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China Faculty of materials science and Engineering Kunming University of Science and TechnologyKunming 650093China

Tuning the charge carrier concentration is imperative to optimize the thermoelectric(TE)performance of a *** BiCuseO based oxyselenides,doping efforts have been limited to optimizing the carrier *** the present work,dual-doping of In and Pb at Bi site is introduced for p-type BiCuseO to realize the electric transport channels with intricate band characteristics to improve the power factor(PF).Herein,the impurity resonant state is realized via doping of resonant dopant In over Pb,where Pb comes forward to optimize the Fermi energy in the dual-doped BiCuseO system to divulge the significance of complex electronic *** manifold roles of dual-doping are used to adjust the elevation of the PF due to the significant enhancement in electrical ***,the combined experimental and theoretical study shows that the In/Pb dual doping at Bi sites gently reduces bandgap,introduces resonant doping states with shifting down the Fermi level into valence band(VB)with a larger density of state,and thus causes to increase the carrier concentration and effective mass(m*),which are favorable to enhance the electronic transport *** a result,both improved ZTmax=0.87(at 873 K)and high ZTave=0.5(at 300–873 K)are realized for InyBi(1−x)−yPbxCuseO(where x=0.06 and y=0.04)*** obtained results successfully demonstrate the effectiveness of the selective dual doping with resonant dopant inducing band manipulation and carrier engineering that can unlock new prospects to develop high TE materials.

关键词： thermoelectric material BiCuseO dual-doping power factor figure of merit