Kane Fermion in a Two-Dimensional π-Conjugated Bis(iminothiolato)nickel Monolayer

Abstract

Massless Kane fermions revealed in zinc-blende semiconductors have recently gained interest in the broad study of relativistic materials. In particular, two-dimensional (2D) Kane fermions were expected to be hybrids of pseudospin-1 and -1/2 Dirac fermions. Based on first-principles calculations, we demonstrated that 2D Kane fermions can be realized in a recently synthesized metal-organic framework, namely, bis(iminothiolato)nickel monolayer. A slight compression takes the system from a semimetal to a semiconductor. At the critical strain of ∼1%, the upper and lower conical bands linearize and touch at a single point intersecting a flat band, showing the same dispersion as the pseudospin-1 Dirac-Weyl systems. We adopted a tight-binding Hamiltonian of a line-centered honeycomb lattice to reveal the origins and topology of the electronic band structure. The coexistence of Kane-type and Dirac-type spectra in the bis(iminothiolato)nickel monolayer is expected to benefit the study of multi quasiparticle effects.

Flatband Line States in Photonic Super‐Honeycomb Lattices

“…Such lattice structures were initially studied more than two decades ago in electronic systems, [ 40,41 ] and were recently revisited by theorists studying their Dirac cones, conical diffraction and massless Kane fermions. [ 42–45 ] One wonders if the composite sHCL could also be realized in experiment, and how its qualitatively different band structure would affect the NLSs.…”

Robust Dirac spin gapless semiconductors in a two-dimensional oxalate based organic honeycomb-kagome lattice

“…Using the same PBE method, the v F value of graphene is calculated to be 7.25 × 10 5 m s −1 , which is in the same order of magnitude of those for Ni 2 (C 2 O 4 ) 3 and Re 2 (C 2 O 4 ) 3 . Moreover, the v F values of Ni 2 (C 2 O 4 ) 3 and Re 2 (C 2 O 4 ) 3 are comparable and even larger than those of most of the previously reported 2D MOFs, such as Ni 2 C 24 S 6 H 12 , 11 bis(iminothiolato)nickel monolayer, 46 Mn 2 C 6 S 12 , 13 Mn 2 C 6 Se 12 14 and Mn 2 C 6 S 6 Se 6 , 14 whose v F values are in the range of 0.3 × 10 5 m s −1 to 2.29 × 10 5 m s −1 .…”

Chern insulator with a nearly flat band in the metal-organic-framework-based Kagome lattice

“…Further, the Fermi level is pinned right above the bottom flat band and the system becomes half-metallic semi-metal, when calculated without SOC. Interestingly, two conical bands and the nearly flat hole band near the zone center show typical Kane model type band alignment 45,46 . At U = 0 eV, the system shows typical three bands above Fermi level.…”