Controllable thermal radiation from twisted bilayer graphene

Far-field thermal properties of β12 borophene under an external electric field

“…By applying a Fourier transform, Π < μν in ( q ⊥ , z ), a mixed representation can be obtained as D a ( r ) νm is the advanced (retarded) GF and D a = ( D r ) † , the retarded GF D r in a ( q ⊥ , z ) mixed representation, can be obtained asBy substituting the retarded GF D r in eqn (14) and the current–current correlation Π < μν in eqn (13) into eqn (11), the derivative terms in eqn (10) can be written asUsing the fluctuation–dissipation theorem, we can obtain Π < ( ω ) = N ( ω )(Π r ( ω ) − Π a ( ω )), where N ( ω ) is the Bose distribution function. 26 The relation between optical conductivity and current–current correlation is Π r αβ ( ω ) = − iωσ αβ ( ω ). The total energy radiation spectrum 35,36 can be obtained by substituting eqn (15) into eqn (10)Here ε 0 is dielectric constant, c is the speed of light, and σ xx ( yy ) ( ω ) is the xx ( yy ) component of optical conductivity.…”

“…, where N(o) is the Bose distribution function. 26 The relation between optical conductivity and current-current correlation is P r ab (o) = Àios ab (o). The total energy radiation spectrum 35,36 can be obtained by substituting eqn (15) into eqn (10)…”

“…Recently, the optical properties of borophene have been studied by some researchers: such as the valley-dependent magneto-optical absorption in monolayer 8- Pmmn borophene, 21 the optical conductivity of monolayer β 12 borophene in the presence of an inversion symmetry breaking field, 22 and the optoelectronic properties of buckled borophene by strain and surface functionalization. 23 Furthermore, the far-field radiation properties can be studied based on the optical conductivity of 2D materials, such as the far-field radiation of monolayer PbBiI, 24 graphene, 25,26 and silicene. 27…”

“…Recently, the optical properties of borophene have been studied by some researchers: such as the valley-dependent magneto-optical absorption in monolayer 8-Pmmn borophene, 21 the optical conductivity of monolayer b 12 borophene in the presence of an inversion symmetry breaking field, 22 and the optoelectronic properties of buckled borophene by strain and surface functionalization. 23 Furthermore, the far-field radiation properties can be studied based on the optical conductivity of 2D materials, such as the far-field radiation of monolayer PbBiI, 24 graphene, 25,26 and silicene. 27 The main aim of this work is to use the tight-binding model, linear response theory, and non-equilibrium Green's function to theoretically calculate the following: (i) the energy band structure of b 12 borophene in the three models and to pay more attention to the high-symmetry points in the Brillouin zone; (ii) the interband and intra-band optical conductivity in the absence and presence of an external electric field; (iii) the radiation spectrum and far-field energy radiation.…”

Twist-induced Casimir Attractive-Repulsive Transition Based on Lithium Iodate

“…Twisted systems are characterized by their unique physical properties resulting from the relative rotational angles in multilayer structure. − In these systems, the twisting of the layers alters the electronic structure and optical properties of the materials, leading to a range of novel quantum phenomena. For instance, in bilayer graphene systems, superconductivity can be induced when the twist angle reaches a “magic angle”. , These phenomena are crucial for exploring new physical states and for advancing technological developments.…”