The type-I, III nodal ring, type-I, III quadratic nodal point, and Dirac valley phonons in 2D kagome lattices MC(M = As, Bi, Cd, Hg, P, Sb, Zn).

Topological phases in kagome systems have garnered considerable interest since the introduction of the colloidal kagome lattice. Our study employs first-principle calculations and symmetry analysis to predict the existence of ideal type-I, III nodal rings (NRs), type-I, III quadratic nodal points (QNPs), and Dirac valley phonons (DVPs) in a collection of two-dimensional (2D) kagome lattices MC(M = As, Bi, Cd, Hg, P, Sb, Zn). Specifically, the Dirac valley points (DVPs) can be observed at two inequivalent valleys with Berry phases of +and-π, connected by edge arcs along the zigzag and armchair directions.

Spin caloritronics in armchair silicene nanoribbons with sp and sp -type alternating hybridizations.

Finite-layer nanoribbon materials have long been considered as potential candidates for nanodevices with novel quantum effects. Here we constructed a series of ferromagnetic armchair silicene nanoribbons (ASiNRs) with sp and sp -type alternating hybridizations, and found that the ASiNRs with different widths are localized in different spin-resolved electronic states. As the width parameter N is increased from 5 to 22, the ASiNR transits from indirect-gap half metallicity (HM), to indirect-gap spin semiconductor (SC), then to direct-gap SC and finally to direct-gap HM.

The spin-dependent Seebeck effect and the charge and spin figure of merit in a hybrid structure of single-walled carbon nanotubes and zigzag-edge graphene nanoribbons.

A hybrid structure of carbon nanotubes and graphene nanoribbons was predicted and synthesized (Y. Li et al., Nat.