The European Physical Journal B最新文献_第2页

Density functional theory study on structural, mechanical, electronic, and phonon properties of CrAlB, MoAlB, WAlB, CrAlGa, MoAlGa, and WAlGa ternary compounds 关于 CrAlB、MoAlB、WAlB、CrAlGa、MoAlGa 和 WAlGa 三元化合物的结构、机械、电子和声子特性的密度泛函理论研究

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-03-06 DOI: 10.1140/epjb/s10051-025-00876-8

B. O. Mnisi

{"title":"Density functional theory study on structural, mechanical, electronic, and phonon properties of CrAlB, MoAlB, WAlB, CrAlGa, MoAlGa, and WAlGa ternary compounds","authors":"B. O. Mnisi","doi":"10.1140/epjb/s10051-025-00876-8","DOIUrl":"10.1140/epjb/s10051-025-00876-8","url":null,"abstract":"<div><p>In this study, we present the structural, mechanical, electronic, and optical properties of CrAlB, MoAlB, WAlB, CrAlGa, MoAlGa, and WAlGa compounds using first-principles density functional theory calculations. We assessed structural stability through heat of formation and found that most compounds have negative heat of formation indicating thermodynamic stability, except for MoAlGa and WAlGa. The elastic constants and moduli indicate that all CrAlB, MoAlB, WAlB, CrAlGa, MoAlGa, and WAlGa compounds are mechanically stable, exhibit elastic anisotropic behavior, relatively machinable, and mixed bonding characteristics with both ionic and covalent contributions. The MAlB (M = Cr, Mo, W) compounds display a brittle nature, whereas MAlGa exhibits ductile behavior. Analysis of Vickers hardness indicate that MAlB compounds are hard compared to MAlGa. The electronic band structures and density (DOS) of states indicate a clear metallic nature in both MAlGa and MAlB compounds. The electronic density difference plots indicate a spherical charge distribution with ionic bonding in MAlB and oblate charge distribution showing covalent bonding in MAlGa. Phonon dispersion analysis demonstrated dynamic stability in MAlB compounds, while MAlGa are dynamically unstable. We note that MAlB compounds are thermodynamically, mechanically, and dynamically stable, making them suitable for high-temperature structural applications such as aerospace and gas turbine engines.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjb/s10051-025-00876-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic impurities in an altermagnetic metal 变磁性金属中的磁性杂质

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-03-06 DOI: 10.1140/epjb/s10051-025-00890-w

Yu-Li Lee

{"title":"Magnetic impurities in an altermagnetic metal","authors":"Yu-Li Lee","doi":"10.1140/epjb/s10051-025-00890-w","DOIUrl":"10.1140/epjb/s10051-025-00890-w","url":null,"abstract":"<p>We study the physics of dilute magnetic impurities in a two-dimensional altermagnetic metal. For the single impurity case, although the spin degeneracy is broken in an altermagnetic metal, we show that the antiferromagnetic Kondo coupling still flows to the strong coupling regime at low energies in terms of the one-loop renormalization-group equation. Moreover, the Kondo temperature may be enhanced or reduced, depending on whether or not the Fermi level is close to the Van Hove singularity at zero altermagnetic coupling. To study the ground-state properties, we employ the variational wavefunction approach. We find that the impurity spin is completely screened at long distances, in contrast to the usual antiferromagnet. The <i>d</i>-wave nature of the spin-split Fermi surfaces in an altermagnetic metal is reflected in the correlation between the impurity and conduction electron spins, which exhibits the <span>(C_{4z})</span> symmetry of the altermagnet at long distances. The spin correlation decays as <span>(1/r^3)</span> at long distances, and its amplitude oscillates with four different periods due to the interference between the spin splitting Fermi surfaces. Moreover, the values of these periods depend on the direction of observation. Similar phenomena also occur in the RKKY interaction in an AM metal.</p><p>The Fermi surface in an altermagnetic metal is split (left). Although a magnetic impurity in an altermagnetic metal is completely screened, the spin correlation between it and the conduction electrons exhibits nontrivial angular dependence (middle) ndue to the interference between spin-split Fermi surfaces. Similar behavior is also shown in the RKKY interaction (right).</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143564418","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}

引用次数: 0

Orientation of active particles in gradient fields

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-03-06 DOI: 10.1140/epjb/s10051-025-00864-y

Yuheng Zhong, Weirong Zhong

{"title":"Orientation of active particles in gradient fields","authors":"Yuheng Zhong, Weirong Zhong","doi":"10.1140/epjb/s10051-025-00864-y","DOIUrl":"10.1140/epjb/s10051-025-00864-y","url":null,"abstract":"<div><p>We used non-equilibrium molecular dynamics simulations to investigate the effects of the orientation of dumbbell-shaped active particles. Self-driven dumbbell particles are situated between two particle reservoirs connected by a channel. By setting different environmental temperatures or particle concentrations in the two reservoirs, a non-equilibrium state with a temperature or concentration gradient is induced in the channel. It is found that the magnitude of the orientation of the active particles is directly proportional to the strength of the gradient field. The direction of the orientation is in line with the temperature gradient but opposite to the concentration gradient. Moreover, the orientation of active particles is also proportional to the self-propulsion force, while Brownian particles do not exhibit any orientation. The length of the dumbbell particle also has an impact on its orientation. When the spacing is zero, resulting in circular active particles, the orientational effect disappears. Additionally, we explored the potential limitations of traditional statistical mechanics methods in self-propelled particle systems. Our research contributes to a deeper understanding of the relationship between self-propulsion forces and the orientation of active particles.</p><h3>Graphical abstract</h3><p>Using non-equilibrium molecular dynamics, we have conducted a thorough investigation into the intricate relationships governing the orientation of active particles. Notably, the orientation aligns with the temperature gradient but opposes the concentration gradient, offering a unique insight into the behavior of these particles under varying conditions. Furthermore, we observed a positive correlation between the self-propulsion force of active molecules and their orientation. This correlation underscores the significance of self-propulsion in dictating the orientational behavior of these particles, which is absent in Brownian particles.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553731","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}

引用次数: 0

Probing the influence of hopping dimerization on persistent currents in cylindrical multi-channel systems

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-03-05 DOI: 10.1140/epjb/s10051-025-00892-8

Ipshita Baruah, Anushka Patowary, Sudin Ganguly

引用次数: 0

Exploring the electronic, elastic anisotropy, and thermodynamic properties of Li2SiO3 and Li2GeO3 compounds using first-principles calculations 利用第一原理计算探索 Li2SiO3 和 Li2GeO3 化合物的电子、弹性各向异性和热力学性质

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-03-02 DOI: 10.1140/epjb/s10051-025-00886-6

Jian-Li Ma, Zhi-Gang Fan, Qun Wei

{"title":"Exploring the electronic, elastic anisotropy, and thermodynamic properties of Li2SiO3 and Li2GeO3 compounds using first-principles calculations","authors":"Jian-Li Ma, Zhi-Gang Fan, Qun Wei","doi":"10.1140/epjb/s10051-025-00886-6","DOIUrl":"10.1140/epjb/s10051-025-00886-6","url":null,"abstract":"<div><p>The first-principles calculation was employed to investigate the electronic structure, mechanical properties, and thermodynamic properties of Li<sub>2</sub>SiO<sub>3</sub> and Li<sub>2</sub>GeO<sub>3</sub> compounds. The optimized lattice parameters and atomic positions are in good agreement with the available experiment datas. The calculated formation enthalpy and elastic constant indicated that Li<sub>2</sub>SiO<sub>3</sub> and Li<sub>2</sub>GeO<sub>3</sub> compounds were thermodynamic and mechanical stability, respectively. The elastic properties, including bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio, were computed based on the obtained elastic constants. Furthermore, the elastic anisotropy was characterized by the graphs of three-dimensional (3D) surface constructions of elastic modulus. Finally, the longitudinal sound velocity, transverse sound velocity, Debye temperature, and minimum thermal conductivity were estimated by the elastic moduli. The obtained results can provide the relevant support of physical parameters for the development and application of Li<sub>2</sub>SiO<sub>3</sub> and Li<sub>2</sub>GeO<sub>3</sub> compounds.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 3","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529947","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}

引用次数: 0

Speech perception: a model of word recognition

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-02-27 DOI: 10.1140/epjb/s10051-025-00882-w

Jean-Marc Luck, Anita Mehta

引用次数: 0

Single-particle spectrum of doped (textrm{C}_{20}textrm{H}_{12})-perylene

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-02-25 DOI: 10.1140/epjb/s10051-024-00859-1

Marcel Rodekamp, Evan Berkowitz, Christoph Gäntgen, Stefan Krieg, Thomas Luu, Johann Ostmeyer, Giovanni Pederiva

引用次数: 0

Optical high harmonic generation in Dirac materials

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-02-21 DOI: 10.1140/epjb/s10051-025-00885-7

S. Rakhmanov, K. Matchonov, H. Yusupov, K. Nasriddinov, D. Matrasulov

引用次数: 0

Influence of vertical throughflow on the linear and nonlinear stability analyses of Rayleigh–Bénard convection in a biviscous Bingham fluid saturating a porous medium

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-02-20 DOI: 10.1140/epjb/s10051-025-00884-8

Pankaj Barman, D. Srinivasachrya, Dipak Barman

{"title":"Influence of vertical throughflow on the linear and nonlinear stability analyses of Rayleigh–Bénard convection in a biviscous Bingham fluid saturating a porous medium","authors":"Pankaj Barman, D. Srinivasachrya, Dipak Barman","doi":"10.1140/epjb/s10051-025-00884-8","DOIUrl":"10.1140/epjb/s10051-025-00884-8","url":null,"abstract":"<p>This article aims to investigate the influence of vertical throughflow on the stability analysis of a biviscous Bingham fluid-saturated horizontal porous layer. Specifically, both linear and nonlinear stability thresholds are examined. The Darcy–Brinkman law is employed to formulate the momentum equation for the system. In this study, all three types of boundary conditions are considered: rigid-rigid, rigid-free, and free-free. The well-known energy method is applied to conduct the nonlinear stability analysis, while the linear stability analysis is carried out using the normal mode approach. The resultant eigenvalue problems are solved using the <i>bvp4c</i>-scheme in MATLAB 2022(a). The critical Rayleigh number and the corresponding wave numbers are obtained numerically by minimizing the neutral stability curves for both theories, and are calculated for the specified values of the flow-governing parameters, with the results presented graphically. It is observed that an increase in the Péclet number (vertical throughflow) delays the onset of convection, whereas an increase in the biviscous Bingham fluid parameter accelerates the onset of convection.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143455403","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}

引用次数: 0

Impact of rare-earth doping on tin disulfide for photocatalytic applications: a first principles insight

IF 1.6 4区物理与天体物理

The European Physical Journal B Pub Date : 2025-02-20 DOI: 10.1140/epjb/s10051-025-00874-w

Mohammed Mjahed, Hicham Bouda, El Mostafa Benchafia, El Mehdi Salmani, Hamid Ez-Zahraouy, Abdelilah Benyoussef

{"title":"Impact of rare-earth doping on tin disulfide for photocatalytic applications: a first principles insight","authors":"Mohammed Mjahed, Hicham Bouda, El Mostafa Benchafia, El Mehdi Salmani, Hamid Ez-Zahraouy, Abdelilah Benyoussef","doi":"10.1140/epjb/s10051-025-00874-w","DOIUrl":"10.1140/epjb/s10051-025-00874-w","url":null,"abstract":"<p>The optoelectronic and photocatalytic properties of rare-earth components (RE<span>(=)</span> Ce, La, and Sm) incorporated into the <span>(hbox {SnS}_2)</span> structure were investigated using first principles simulations. The TB-mBJ (Tran–Blaha modified Becke–Johnson) approach was used to explore several novel properties. The observed electronic band gap energy of pure <span>(hbox {SnS}_2)</span> is <span>(E_g = 2.4)</span> eV, which is in good agreement with the reported experimental value of <span>(E_g = 2.44)</span> eV. Results show that doping <span>(hbox {SnS}_2)</span> with RE elements at a concentration of 6.25% significantly reduces the electronic band gap compared to pristine <span>(hbox {SnS}_2)</span>. This reduction can be attributed to the smaller ionic radii of <span>(hbox {Ce}^{3+})</span>, <span>(hbox {La}^{3+})</span>, and <span>(hbox {Sm}^{3+})</span> ions, as well as the appearance of new states hybridized by RE-4f within the band gap, leading to a remarkable enhancement of the absorption spectra in the visible light range. Additionally, the calculated edge positions of the conduction band minimum (CBM) and the valence band maximum (VBM) relative to the normal hydrogen electrode (NHE) for both pristine and RE-doped <span>(hbox {SnS}_2)</span> are optimal for water splitting. Consequently, doping <span>(hbox {SnS}_2)</span> with rare-earth elements appears to be a promising strategy for enhancing its photocatalytic activity in the visible light spectrum.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143455456","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}

引用次数: 0