Third-order optical nonlinearities of chiral graphene tubules

The nonlinear optical properties of coupling and decoupling graphene layers

“…6(b), indicating the coupling takes more effect upon the nonlinear refraction than the nonlinear absorption. It is well documented in the literature that large complex delocalized π -electron systems show good nonlinearities, such as some organic molecules, fullerenes C n , carbon nanotubes [23][24][25] and graphene of course. The coupling of graphene layers could change the band structure considerable (for example, the band structure of the bi-layer graphene is not the linear dispersion any more) and increase the intraband electronic scattering, leading to the delocalization weakening of the π -band electron and reducing the nonlinearities consequently.…”

Effect of the Encapsulation ofM(M=Cs,Li and Na) Atom on Spin Dependent Transport of C60Cage

“…In the Numerical calculation we take: t 0 = 2.5 eV and α 0 = 4.85, 4.7 and 3.99eV/ Å, 1 β = 0.55, 0.46, 0.45 Å for Cs, Li and Na ions, respectively, U 0 = t 0 , V 0 = 0 and T = 300K [34]. We also used parameters from Reference (35).…”

“…The hopping parameters t i α ,j α between the electrodes and the channel are taken to be t. The last term describes Hamiltonian of the central part that can be extended as (33)(34)(35)(36):…”

“…Using the charge density, the central part Hamiltonian and the Green's function on every atom in the channel should be iteratively calculated until a convergence of the change of the bond length is reached (33,34). Also, the current is determined consistently under nonequilibrium condition at every bias voltage.…”

Theoretical study on photophysical property of C60M(CO)5 (M=Cr, Mo and W)

“…Among such known fullerene metal complexes, some molybdenum and tungsten η 2 models of [60]fullerene derivatives have been reported [11][12][13][14] . On the other hand, the nonlinear optical properties of fullerenes, their derivatives and carbon nanotubes have been widely investigated [15][16][17][18][19][20] . The chemical-modified fullerene and endohedral fullerene materials can show enhancement on their third-order optical nonlinearity compared to small host fullerene molecules.…”