Quantum anomalous vortex and Majorana zero mode in iron-based superconductor Fe(Te,Se)

In topological insulators doped with magnetic ions, spin-orbit coupling and ferromagnetism give rise to the quantum anomalous Hall effect. Here we show that in s-wave superconductors with strong spin-orbit coupling, magnetic impurity ions can generate topological vortices in the absence of external magnetic fields. Such vortices, dubbed quantum anomalous vortices, support robust Majorana zero-energy modes when superconductivity is induced in the topological surface states. We demonstrate that the zero-energy bound states observed in Fe(Te,Se) superconductors are possible realizations of the Majorana zero modes in quantum anomalous vortices produced by the interstitial magnetic Fe. The quantum anomalous vortex matter not only advances fundamental understandings of topological defect excitations of Cooper pairing, but also provides new and advantageous platforms for manipulating Majorana zero modes in quantum computing.Comment: final version, 8 pages, 3 figures + supplemental materia

Pole expansion of self-energy and interaction effect on topological insulators

We study effect of interactions on time-reversal-invariant topological insulators. Their topological indices are expressed by interacting Green's functions. Under the local self-energy approximation, we connect topological index and surface states of an interacting system to an auxiliary noninteracting system, whose Hamiltonian is related to the pole-expansions of the local self-energy. This finding greatly simplifies the calculation of interacting topological indices and gives an noninteracting pictorial description of interaction driven topological phase transitions. Our results also bridge studies of the correlated topological insulating materials with the practical dynamical-mean-field-theory calculations.Comment: 4.2 pages, 3 figures, reference added, typos correcte

Research on Spatial Planning Layout of Inclusive Pre-school Education Resources in Chengdu City

With the population gathering in urban centers, the spatial distribution of preschool education resources is becoming increasingly important. Families want their children to receive education at the kindergartens located near their homes. Public kindergartens and inclusive private kindergartens recognized by districts (cities) and counties are important components of the public preschool education system. In 2012, the State Council published the "Twelfth Five-Year Plan for the National Basic Public Service System", which first clarified the concept definition of basic public services, that is, services provided by the government based on social consensus, in line with the level of social and economic development, and aimed at meeting the survival and development needs of all citizens. Therefore, it can be judged that preschool education is an important basic public service. To solve the current problem of unreasonable spatial distribution of preschool education resources, Chengdu has proposed the goal of building a "15-minute preschool education service circle", by rational planning and layout, to increase the coverage and utilization rate of preschool education resources, and meet the needs of families for preschool education. This study, through analyzing the new trends of population mobility in various districts (cities) and counties in Chengdu and the allocation of preschool education resources, found that the coverage rate of inclusive kindergartens in Chengdu has reached more than 85%, and the proportion of children in public kindergartens has basically reached 50%

Spin current through an ESR quantum dot: A real-time study

The spin transport in a strongly interacting spin-pump nano-device is studied using the time-dependent variational-matrix-product-state (VMPS) approach. The precession magnetic field generates a dissipationless spin current through the quantum dot. We compute the real time spin current away from the equilibrium condition. Both transient and stationary states are reached in the simulation. The essentially exact results are compared with those from the Hartree-Fock approximation (HFA). It is found that correlation effect on the physical quantities at quasi-steady state are captured well by the HFA for small interaction strength. However the HFA misses many features in the real time dynamics. Results reported here may shed light on the understanding of the ultra-fast processes as well as the interplay of the non-equilibrium and strongly correlated effect in the transport properties.Comment: 5 pages, 5 figure

Derivation of Electroweak Chiral Lagrangian from One Family Technicolor Model

Based on previous studies deriving the chiral Lagrangian for pseudo scalar mesons from the first principle of QCD in the path integral formalism, we derive the electroweak chiral Lagrangian and dynamically compute all its coefficients from the one family technicolor model. The numerical results of the $p^4$ order coefficients obtained in this paper are proportional to the technicolor number $N_{\rm TC}$ and the technifermion number $N_{\rm TF}$, which agrees with the arguments in previous works, and which confirms the reliability of this dynamical computation.Comment: 6 page

Teachers’ Classroom Discourse Pattern for Postgraduates Majoring in Foreign Linguistics: A Perspective of Legitimation Code Theory

“Introduction to English Linguistics (IEL)” is a professional knowledge course for postgraduates majoring in Foreign Linguistics. In traditional classrooms, teachers usually use knowledge code in their discourse, emphasizing the inculcation of theoretical knowledge in Foreign Linguistics. However, faced with large numbers of concepts, terminology, and academic opinions, students generate lots of confusion. This study quantitatively analyzes the teaching situation of IEL course under the framework of Legitimation Code Theory, and explores the influence of different teachers’ classroom discourse patterns on students’ learning efficiency. It is found that the use of knower code in teachers’ classroom discourse is an important factor in students’ learning efficiency while not being affirmatively proved to be effective in a pronounced manner, suggesting that a more advanced model of teachers’ classroom discourse pattern combining both knowledge code and knower code for postgraduates majoring in Foreign Linguistics is urgently needed