Extreme sensitivity of the electric-field-induced band gap to the electronic topological transition in sliding bilayer graphene

Unique electronic and optical properties of stacking-modulated bilayer graphene under external magnetic fields

This study delves into the magneto-electronic and magneto-optical properties of stacking-modulated bilayer graphene. By manipulating domain walls (DWs) across AB-BA domains periodically, we unveil oscillatory Landau subbands and the associated optical excitations. The DWs act as periodic potentials, yielding fascinating 1D spectral features. Our exploration reveals 1D phenomena localized to Bernal stacking, DW regions, and stacking boundaries, highlighting the intriguing formation of Landau state quantization influenced by the commensuration between the magnetic length and the system. The stable quantized localization within different regions leads to the emergence of unconventional quantized subbands. This study provides valuable insights into the essential properties of stacking-modulated bilayer graphene.

ZnGeSb2: a promising thermoelectric material with tunable ultra-high conductivity

First principles calculations predict the promising thermoelectric material ZnGeSb₂ with a huge power factor (S²σ/τ) on the order of 3 × 10¹⁷ W m^-1 K^-2 s^-1, due to the ultra-high electrical conductivity scaled by a relaxation time of around 8.5 × 10²⁵ Ω^-1 m^-1 s^-1, observed in its massive Dirac state. The observed electrical conductivity is higher than the well-established Dirac materials, and is almost carrier concentration independent with similar behaviour of both n and p type carriers, which may certainly attract device applications. The low range of thermal conductivity is also evident from the phonon dispersion. Our present study further reports the gradual phase change of ZnGeSb₂ from a normal semiconducting state, through massive Dirac states, to a topological semi-metal. The maximum power factor is observed in the massive Dirac states compared to the other two states.