Related papers: Optical absorption tensors based on C$_{70}$ trime…
With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar's environment in absorption. We used a sample of 17 Lyman limit systems with column density N_HI > 10^19 cm^-2…
Surface adsorption of C$_{60}$ affects its chemical and electronic properties. Numerous studies have reported observation of bright and dark fullerenes on metal surfaces that suggest extensive surface reconstruction, however, the…
We present photoabsorption oscillator strengths for C3H6 molecules with emphasis on the difference between isomers, cyclopropane and propylene. We use an iterative numerical method based on the time-dependent local density approximation…
Conjugated polymers can be reversibly doped by electrochemical means. This doping introduces new sub-bandgap optical absorption bands in the polymer while decreasing the bandgap absorption. To study this behavior, we have prepared an…
We numerically calculate the optical conductivity of twisted graphene bilayers within the continuum model. To obtain the imaginary part, we employ the regularized Kramers-Kronig relation allowing us to discuss arbitrary twist angles,…
Optical absorption properties of magnetoexcitons in topological insulator bilayers under a strong magnetic field are theoretically studied. A general analytical formula of optical absorption selection rule is obtained in the noninteracting…
A metamaterial composed of thin metallic strips as an efficient broadband absorber in the mid-infrared spectrum is investigated. Here the matching between dielectric and geometrical properties of the individual elements is critical to…
Studying optical properties of organic materials is important due to the rapid development of organic light-emitting diodes, solar cells, and photon detectors. Here for the first time we have performed tight-binding calculations for singlet…
The frequency-dependent conductivity is studied for both the one-dimensional Hubbard model and a model of spinless fermions, using a selection rule, the Bethe ansatz energy eigenstates, and conformal invariance. For densities where the…
The absorption of free linear chains in a polymer brush was studied with respect to chain size $L$ and compatibility $\chi$ with the brush by means of Monte Carlo (MC) simulations and Density Functional Theory (DFT) / Self-Consistent Field…
Low-gap conjugated polymers have enabled an impressive increase in the efficiencies of organic solar cells, primarily due to their red absorption which allows harvesting of that part of the solar spectrum. Here, we report that the true…
The inter-band optical absorption in graphene characterized by its fine-structure constant has a universal value of 2.3\% independent of the material parameters. However, for several graphene-based photonic applications, enhanced optical…
The low-frequency magneto-optical absorption spectra of bilayer Bernal graphene are studied within the tight-binding model and gradient approximation. The interlayer interactions strongly affect the electronic properties of the Landau…
We present results for the optical absorption spectra of small-diameter single-wall carbon and boron nitride nanotubes obtained by {\it ab initio} calculations in the framework of time-dependent density functional theory. We compare the…
The optical absorption spectrum of the three most stable isomers of the Ag11 system was calculated using the time-dependent density functional theory, with the generalized gradient approximation for the exchange and correlation potential,…
Absorbing aerosols, such as brown carbon (BrC) and absorbing secondary organic aerosols (SOA), has attracted broad interest due to their importance for climate and human health. The pronounced time-dependence of light absorption during…
Nonlinear optical properties of extracted higher fullerenes - C70, C76, C78, and C84 - are theoretically investigated. Magnitudes of off-resonant third-harmonic-generation are calculated by the intermediate exciton theory. We find that…
Spectrally-tailored interactions of light with material interfaces offer many exciting applications in sensing, photo-detection, and optical energy conversion. In particular, complete suppression of light reflectance at select frequencies…
We investigate theoretically the phenomenon of exchange narrowing in the absorption spectrum of a chain of monomers, which are coupled via resonant dipole-dipole interaction. The individual (uncoupled) monomers exhibit a broad absorption…
We analyze the rate of two-photon absorption in tapered optical fibers with diameters less than the wavelength of the incident light. The rate of two-photon absorption is shown to be enhanced due to the small mode volume of the tapered…