Phase diagram and quench dynamics of a periodically drivenHaldane model

We investigate a periodically driven Haldane model subjected to a two-stage driving scheme in the form of a step function.By using the Floquet theory,we obtain the topological phase diagram of the system.We also find that anomalous Floquet topological phases exist in the system.Focusing on examining the quench dynamics among topological phases,we analyze the site distribution of the 0-mode and p-mode edge states in long-period evolution after a quench.The results demonstrate that,under certain conditions,the site distribution of the 0-mode can be confined at the edge even in long-period evolution.Additionally,both the 0-mode and p-mode can recover and become confined at the edge in long-period evolution when the post-quench parameters(T,M_(2) /M_(1))in the phase diagram cross away from the phase boundary (M_(2)/ M_(1))=(6√3t2)/ M_(1)−1.Furthermore,we conclude that whether the edge state is confined at the edge in the long-period evolution after a quench depends on the similarity of the edge states before and after the quench.Our findings reveal some new characteristics of quench dynamics in a periodically driven system.

Flavor SU(3)topological diagram and irreducible representation amplitudes for heavy meson charmless hadronic decays:mismatch and equivalence

Flavor SU（3） analysis of B meson charmless hadronic two light pseudoscalar decays can be formulated in two different ways. One is to construct the SU（3） irreducible representation amplitude （IRA） according to effective Hamiltonian transformation properties, and the other is to draw the topological diagrams （TDA）. We first point out that previous analyses of TDA and IRA approaches do not match in several aspects, in particular a few SU（3） independent amplitudes have been overlooked in the TDA approach. This has caused confusions in the past and sometimes resulted in incorrect interpretation of data. We then demonstrate that only if these amplitudes are included, a consistent and unified picture can be obtained. With the new TDA amplitudes, all charmless hadronic decays of heavy meson must have nonzero direct CP symmetries as already predicted by the IRA approach. In addition to their notable impact on CP asymmetry, the new amplitudes are also important to extract new physics information.

Covalent Organic Frameworks for Energy Conversions:Current Status,Challenges,and Perspectives

Energy conversion into clean fuels is critical to society’s health benefits and sustainable future;thus,exploring materials to enable and facilitate energy conversions with reduced climate-related emissions is a central subject of science and technology.Covalent organic frameworks(COFs)are a class of polymers that enables predesign of both primary-and high-order structures and precise synthesis of long-range structures through one-pot polymerization.Progress over the past 15 years in chemistry has dramatically enhanced our capability of designing and synthesizing COFs and deepening our understanding to explore energy-converting functions that originate from their ordered skeletons and channels.In this minireview,we summarize general strategies for predesigning skeletons and channels and analyze the structural requirements for each type of energy conversion.We demonstrate synthetic approaches to develop energy conversion functions,that is,photocatalytic and electrocatalytic conversions.Further,we scrutinize energy conversion features by disclosing interplays of COFs with photons,holes,electrons,and molecules,highlighting the role of structural orderings in energy conversions.Finally,we have predicted the challenging issues in molecular design and synthesis,and thought of future directions toward advancement in this field,and show perspectives from aspects of chemistry,physics,and materials science,aimed at unveiling a full picture of energy conversions based on predesignable organic architectures.

Software System Evolution Analysis Method Based on Algebraic Topology

The analysis of software system evolution is highly significant in software research as the evolution runs throughout the lifecycle of a software system. Considering a software system as an algebraic engineering system, we propose a software system evolution analysis method based on algebraic topology. First, from a complex network perspective, we abstract a software system into the software structural topology diagram. Then, based on the algebraic topology principle, we abstract each node in the software structural topology diagram into an algebraic component represented by a 6-tuple. We propose three kinds of operation relationships between two algebraic components, so that the software system can be abstracted into an algebraic expression of components. In addition, we propose three forms of software system evolution, which help to analyze the structure and evolution of system software and facilitate its maintenance and reconfiguration.