In this study,we propose valley phononic crystals that consist of a hexagonal aluminum plate with six chiral arrangements of ligaments.Valley phononic crystals were introduced into a topological insulator(TI)system to...In this study,we propose valley phononic crystals that consist of a hexagonal aluminum plate with six chiral arrangements of ligaments.Valley phononic crystals were introduced into a topological insulator(TI)system to produce topologically protected edge waves(TPEW s)along the topological interfaces.The implementation of chiral topological edge states is different from the implementation of topological edge states of systems with symmetry.Unlike the conventional breaking of mirror symmetry,a new complete band with topological edge modes gap was opened up at the Dirac point by tuning the difference in lengths of the ligaments in the chiral unit cells.We investigated the dispersion properties in chiral systems and applied the dispersion properties to waveguides on the interfaces to achieve designable route systems.Furthermore,we simulated the robust propagation of TPEWs in different routes and demonstrated their immunity to backscattering at defects.Finally,the existence of the valley Hall effect in chiral systems was demonstrated.The study findings may lead to the further study of the topological states of chiral materials.展开更多
In recent years,there has been growing interest in the study of chiral active materials,which consist of building blocks that show active dynamics featuring chiral symmetry breaking,e.g.,particles that rotate in a com...In recent years,there has been growing interest in the study of chiral active materials,which consist of building blocks that show active dynamics featuring chiral symmetry breaking,e.g.,particles that rotate in a common direction.These materials exhibit fascinating phenomena such as odd viscosity,odd diffusivity,active turbulence in fluids,vivid dislocation dynamics or odd elasticity in crystals or elastic materials,and hyperuniform states.The systematic study of soft chiral active matter systems is relatively new,starting around 2017,but has already shown promising applications in robust cargo transport,segregation and mixing dynamics,or manipulation of metamaterials.In this review,we summarize recent experimental and theoretical advances in this field,highlighting the emergence of anti-symmetric and odd stresses and ensuring effects such as odd viscosity or topologically protected edge modes.We further discuss the underlying mechanisms and provide insights into the potential of chiral active matter for various applications.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11872313 and 12172297).
文摘In this study,we propose valley phononic crystals that consist of a hexagonal aluminum plate with six chiral arrangements of ligaments.Valley phononic crystals were introduced into a topological insulator(TI)system to produce topologically protected edge waves(TPEW s)along the topological interfaces.The implementation of chiral topological edge states is different from the implementation of topological edge states of systems with symmetry.Unlike the conventional breaking of mirror symmetry,a new complete band with topological edge modes gap was opened up at the Dirac point by tuning the difference in lengths of the ligaments in the chiral unit cells.We investigated the dispersion properties in chiral systems and applied the dispersion properties to waveguides on the interfaces to achieve designable route systems.Furthermore,we simulated the robust propagation of TPEWs in different routes and demonstrated their immunity to backscattering at defects.Finally,the existence of the valley Hall effect in chiral systems was demonstrated.The study findings may lead to the further study of the topological states of chiral materials.
基金the National Natural Sience Foundation of China for supporting this project within the Research Fund for International Young Scientists(12350410368)financial support from the Natural Science Foundation of Guangdong Province(2024A1515011343)the Key Project of Guangdong Provincial Department of Education(2023ZDZX3021)
文摘In recent years,there has been growing interest in the study of chiral active materials,which consist of building blocks that show active dynamics featuring chiral symmetry breaking,e.g.,particles that rotate in a common direction.These materials exhibit fascinating phenomena such as odd viscosity,odd diffusivity,active turbulence in fluids,vivid dislocation dynamics or odd elasticity in crystals or elastic materials,and hyperuniform states.The systematic study of soft chiral active matter systems is relatively new,starting around 2017,but has already shown promising applications in robust cargo transport,segregation and mixing dynamics,or manipulation of metamaterials.In this review,we summarize recent experimental and theoretical advances in this field,highlighting the emergence of anti-symmetric and odd stresses and ensuring effects such as odd viscosity or topologically protected edge modes.We further discuss the underlying mechanisms and provide insights into the potential of chiral active matter for various applications.
