3 documents found, page 1 of 1
Low-cost portable sensor for uplastics differentiation
Penso, C. M.; Paiva, M. C.; Viana-Gomes, J.; Rocha, J.L.; Gonçalves, L. M.Na última década, os μplásticos tornaram-se um dos principais problemas de poluição nos oceanos, cursos de água e rios, atraindo atenção devido aos efeitos nocivos que provocam no meio ambiente e na saúde. Os métodos atuais para quantificação de μplásticos incluem imagiologia hiperespectral, espectroscopia de Raman e espectroscopia de infravermelho por transformadade Fourier (FTIR). No entanto, estes equipament...
Solution of the quantum harmonic oscillator plus a delta-function potential at ...
Viana-Gomes, J.; Peres, N. M. R.We derive the energy levels associated with the even-parity wavefunctions of the harmonic oscillator with an additional delta-function potential at the origin. Our results bring to the attention of students a non-trivial and analytical example of a modification of the usual harmonic oscillator potential, with emphasis on the modification of the boundary conditions at the origin. This problem calls the attention...
Faraday effect in graphene enclosed in an optical cavity and the equation of mo...
Ferreira, Aires Francisco Lemos Gonçalves; Viana-Gomes, J.; Bludov, Yuliy V.; Pereira, V.; Peres, N. M. R.; Castro Neto, A. H.We show that by enclosing graphene in an optical cavity, giant Faraday rotations in the infrared regime are generated and measurable Faraday rotation angles in the visible range become possible. Explicit expressions for the Hall steps of the Faraday rotation angle are given for relevant regimes. In the context of this problem we develop an equation of motion (EOM) method for calculation of the magneto-optical p...