Twist-induced magnon Landau levels in honeycomb magnets

Bose-Einstein condensate of Dirac magnons: Pumping and collective modes

“…It is known that a Dirac-like magnon spectrum is generated for localized magnetic moments on a 2D honeycomb lattice [23,27]. Wide range of properties within this emergent class of materials: interaction effects [23,37] that renormalize the slope of the dispersion, topological properties [36,[38][39][40][41][42][43], strain effects [44][45][46] and non-Hermitian dynamics [47] were investigated observed in these materials. While some properties of fermionic and bosonic Dirac materials are similar, there are, of course, crucial differences.…”

Pseudo Landau levels, negative strain resistivity, and enhanced thermopower in twisted graphene nanoribbons

“…1(c)] characterized by the parameter λ = Φ/L that measures the rotational angle of the nanoribbon unit cell [Fig. 1(a)] per unit length along the x direction, we have δ i (r) ≈ (α 2 i + λ 2 α 2 i,x y 2 ) 1/2 for a sufficiently small twist λ a −1 [65]. We note that δ i (r) preserves the modified x-direction translational symmetry Π(δ x ) = T (δ x ) R(λδ x ), which should be defined as a regular translation ( T ) by δ x along the x direction combined with a counter-clockwise rotation ( R) by an angle of λδ x around the x axis [Fig.…”