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Neutrinos in the flavor-dependent U(1)F model

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Physical Review D 2024年第11期110卷 115007-115007页

作者： Jin-Lei Yang Department of Physics Hebei University Baoding 071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding 071002 China and Research Center for Computational Physics of Hebei Province Baoding 071002 China

The neutrino oscillation experiments provide definitive evidence of new physics beyond the Standard Model, and the neutrino mass-squared differences and flavor mixing have been precisely measured. This study examines the neutrino sector within the flavor-dependent U(1)F model, where the unique fermion sector can simultaneously address both the flavor mixing puzzle and the mass hierarchy puzzle. It is found that the lightest neutrino is naturally massless in this model, and the predicted neutrino mass-squared differences, flavor mixing angles, and Dirac CP phase agree well with the experimental measurements. Additionally, the effects of the Dirac CP phase and Majorana CP phase on the theoretical predictions of the neutrino transition magnetic dipole moments are analyzed.

关键词： Neutrino mixing Neutrinos Flavor symmetries Neutrino mass

First order corrections to black hole thermodynamics: A simple approach enhanced

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Physical Review D 2024年第10期110卷 104043-104043页

作者： Yong Xiao Yue-Ying Liu Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College of Physical Science and Technology Hebei University Baoding 071002 China and Hebei Research Center of the Basic Discipline for Computational Physics Baoding 071002 China

The inclusion of higher derivative terms in the gravitational action brings about corrections to the original forms of black hole solutions and thermodynamics. A simple and valuable approach emerged over two decades ago, which states that the first order corrections to black hole thermodynamics, caused by higher derivative terms, can be achieved without explicitly solving the perturbed metric. However, a direct application of this approach may potentially yield incorrect answers as it comes to anti-de Sitter (AdS) black holes, which poses a challenge to the valuable approach. In this paper, we identify that the subtlety associated with AdS black holes is that certain higher derivative terms may alter the asymptotic structure of the spacetime. By taking this subtlety into account, we successfully enhance the original approach and resolve the mentioned problem. Furthermore, we make an interesting observation that the extremalization analysis that underlies this approach also plays a fundamental role in the perturbation theories of quantum mechanics and other disciplines.

关键词： Alternative gravity theories quantum aspects of black holes quantum gravity

Elemental noncentrosymmetric superconductors

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arXiv 2024年

作者： Zhang, Hu Research Center for Computational Physics of Hebei Province Hebei Key Laboratory of High-precision Computation and Application of Quantum Field Theory College of Physics Science and Technology Hebei University Baoding071002 China

Superconductivity has been discovered in many materials including elements, cuprates and nickelates. Noncentrosymmetric superconductors get attention due to their physical properties results from spatial inversion symmetry breaking. Here we propose the existence of elemental noncentrosymmetric superconductors which needs to break spatial inversion symmetry in single element phases realized by occupations of more than one Wyckoff positions. Elemental noncentrosymmetric superconductors allow us to study the admixture of spin-singlet and spin-triplet pairing states in elements with simple crystal structures and chemical conditions. We find that four-layer La thin films coming from bulk α-La with a double hexagonal close-packed structure are elemental noncentrosymmetric superconductors since the dimension reduction breaks the spatial inversion symmetry. In the normal state, four-layer La is a polar rare-earth metal with a spontaneous polarization having a polar layer group like ferroelectrics. Hence, to be more precise, four-layer La can also be called the elemental polar superconductor in the superconductivity state. Based on this method of breaking inversion symmetry, we discovery polar rare-earth metals, polar transition metals, polar alkali metals and polar alkali earth metals. Other candidate materials are bulk polar materials formed with group 15 elements, Bi thin films with polar stacking, polar double layer plumbene and Al thin films. The question of building the periodic table of elemental noncentrosymmetric superconductors is raised. © 2024, CC BY.

关键词： Rare earths

通过键共价性增加策略获得高性能Cu_(3)SbSe_(4)基热电材料

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Science China Materials 2023年第9期66卷 3644-3650页

作者：张旦钟瑞奇高仕康杨磊徐芳何平柳冠楠伞星源杨君友罗裕波王淑芳 Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College of Physics Science and TechnologyHebei UniversityBaoding 071002China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

通过Cu_(3)SbSe_(4)-MTe (M=Ge/Sn)固溶体系的对比研究,本文报道了一种增加键共价性来弱化电声耦合进而获得高迁移率的策略,也证实了该策略能提升Cu_(3)SbSe_(4)化合物的热电性能.研究发现,相比于SnTe固溶,GeTe固溶赋予Cu_(3)SbSe_(4)... 详细信息

通过Cu_(3)SbSe_(4)-MTe (M=Ge/Sn)固溶体系的对比研究,本文报道了一种增加键共价性来弱化电声耦合进而获得高迁移率的策略,也证实了该策略能提升Cu_(3)SbSe_(4)化合物的热电性能.研究发现,相比于SnTe固溶,GeTe固溶赋予Cu_(3)SbSe_(4)化合物在相似载流子浓度情况下更高的迁移率,进而获得更优越的电输运性能.密度泛函理论计算表明,与SnTe固溶相比,GeTe固溶能增加Cu_(3)SbSe_(4)化学键共价性因而具有优越的电输运性能.最终,在Cu_(3)SbSe_(4)-1%GeTe样品中取得了0.8的最大热电优值(@648 K)和0.41的平均热电优值(300–648 K).此研究表明,通过增加键共价性来弱化电声耦合进而获得高迁移率是提升热电性能的有效途径.

关键词：密度泛函理论计算共价性热电性能热电优值高迁移率热电材料载流子浓度

Incorporating element doping and quantum dot embedding effects to enhance the thermoelectric properties of higher manganese silicides

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Journal of Materiomics 2021年第2期7卷 377-387页

作者： Qing Wang Shiyu Song Xiaofeng Yang Ziyang Liu Yufei Ma Xingyuan San Jianglong Wang Dan Zhang Shu-Fang Wang Zhiliang Li Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College of Physics Science and TechnologyHebei UniversityBaoding071002China Institute of Life Science and Green Development Hebei UniversityBaoding071002China

Element doping and nano-inclusion embedding are effective approaches to enhance the electrical conductivities and decrease the lattice thermal conductivities of thermoelectric(TE)materials,***,the intrinsic low electrical thermal conductivities and high electrical properties are severely sacrificed,and the final figure of merit(ZT)is usually *** this study,Ag doping and Pt quantum dot(QD)embedding were synchronously achieved via embedding Ag/Pt alloy QDs into the higher manganese silicides to avoid the conventional single-element doping *** power factor(at 823 K)was enhanced from 1.57×10^(-3) W m^(-1) K^(-2) to 1.82×10^(-3) W m^(-1) K^(-2)(-16%)due to the-18%increase in carrier concentration that was derived from the Ag doping ***,the lattice thermal conductivity(at 823 K)decreased from 2.65 W m^(-1) K^(-1) e1.92 W m^(-1) K^(-1)(-28%)because of the broadband phonon scattering effect that resulted from the residual Pt QDs ***,the optimal ZT value increased by-52%from 0.42 to 0.64 at 823 *** study demonstrated that incorporating metastable alloy QDs to obtain element doping and nano-inclusion embedding effects is a novel and feasible means to enhance the ZT value of *** method is also possibly applicable to other alloy QD/TE composites.

关键词： quantum dot Inclusion higher manganese silicide Thermoelectric material Figure of merit

The flavor-dependent U(1)F model

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arXiv 2024年

作者： Yang, Jin-Lei Zhang, Hai-Bin Feng, Tai-Fu Department of Physics Hebei University Baoding071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding071002 China Research Center for Computational Physics of Hebei Province Baoding071002 China

A flavor-dependent model (FDM) is proposed in this work. The model extends the Standard Model by an extra U(1)F local gauge group, two scalar doublets, one scalar singlet and two right-handed neutrinos, where the additional U(1)F charges are related to the particles’ flavor. The new fermion sector in the FDM can explain the flavor mixings puzzle and the mass hierarchy puzzle simultaneously, and the nonzero Majorana neutrino masses can be obtained naturally by the Type I see-saw mechanism. In addition, the B meson rare decay processes B¯ → Xsγ, Bs0 → µ+µ−, the top quark rare decay processes t → ch, t → uh and the τ lepton flavor violation processes τ → 3e, τ → 3µ, µ → 3e predicted in the FDM are analyzed. © 2024, CC BY.

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Neutrinos in the flavor-dependent U(1)F model

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arXiv 2024年

作者： Yang, Jin-Lei Li, Jie Department of Physics Hebei University Baoding071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding071002 China Research Center for Computational Physics of Hebei Province Baoding071002 China

The neutrino oscillation experiments provide definitive evidence of new physics beyond the Standard Model (SM), and the neutrino mass-squared differences and flavor mixing have been precisely measured. This study examines the neutrino sector within the flavor-dependent U(1)F model, where the unique fermion sector can simultaneously address both the flavor mixing puzzle and the mass hierarchy puzzle. It is found that the lightest neutrino is naturally massless in this model, and the predicted neutrino mass-squared differences, flavor mixing angles, Dirac CP phase agree well with the experimental measurements. Additionally, the effects of the Dirac CP phase and Majorana CP phase on the theoretical predictions of the neutrino transition magnetic dipole moments are analyzed. © 2024, CC BY.

关键词： Neutrons

A mechanism relating the fermionic mass hierarchy to the flavor mixing

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arXiv 2024年

Considering the hierarchical structure of fermionic masses and the fermionic flavor mixing puzzles in the Standard Model, we propose to relate them by the see-saw mechanism, i.e. only the third generation of quarks and charged leptons achieve the masses at the tree level, the first two generations achieves masses through the mixings with the third generation, and the neutrinos achieve tiny Majorana masses by the so-called Type-I see-saw mechanism. This new picture at the fermion sector can explain simultaneously the flavor mixing puzzle and mass hierarchy puzzle in the SM. In addition, a flavor-dependent model (FDM) is proposed to realize the new mechanism, and observing the top quark rare decay processes t → ch, t → uh and the lepton flavor violation processes µ → 3e, τ → 3e, µ → 3µ is effective to test the proposed FDM. © 2024, CC BY.

关键词： Mixing

Explaining the possible 95 GeV excesses in the B-L symmetric SSM

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arXiv 2024年

作者： Yang, Jin-Lei Guo, Ming-Hui Zhang, Wen-Hui Zhang, Hai-Bin Feng, Tai-Fu Department of Physics Hebei University Baoding071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding071002 China Research Center for Computational Physics of Hebei Province Baoding071002 China

This study investigates the excesses observed in the diphoton and bb¯ data around 95 GeV within the framework of the B − L supersymmetric model (B-LSSM). Comparing with the minimal supersymmetric standard model, the B-LSSM incorporates two singlet chiral Higgs bosons which mix with the SM-like Higgs boson due to the gauge kinetic mixing effect. The richer Higgs sector indicates that designating the B-LSSM specific CP-even Higgs state as the lightest Higgs boson has great potential to explain the excesses at around 95 GeV. Considering the two-loop effective potential corrections to the squared Higgs mass matrix, it is found that the signal strengthes µ(h95)γγ, µ(h95)bb can be described simultaneously in the experimental 1σ interval. And the B-LSSM specific parameters tan β′, Bη, gY B, MZ′ affect the theoretical predictions on the light Higgs boson masses and signal strengthes µ(h95)γγ, µ(h95)bb significantly. © 2024, CC BY.

关键词： Bosons