von Parinda Vasa ; Robert Pomraenke ; Stephan Schwieger ; Yuriy I. Mazur ; Vasyl Kunets ; P. Srinivasan ; E. Johnson ; Erich Runge ; Gregory J. Salamo ; Christoph Lienau
The far-field reflectivity of metallic nanowire arrays designed to show strong surface-plasmon-polariton (SPP) resonances is studied numerically. The results of calculations in time and frequency space as well as the results of semi-analytic theories using different approximative boundary conditions at the metal surfaces are evaluated and compared. Good agreement between all different methods is obtained in most cases. The SPP-related features are superimposed on a strongly varying background. Combining FDTD simulations, finite element results, and semi-analytical calculations, the microscopic origin of the background contribution is identified. Resonant transmission through sub-wavelength slits leads to pronounced oscillations in the far-field reflectivity as a function of the height of the nanowires.
International journal of modern physics / B Singapore [u.a.] : World Scientific Publ., 1987 22(2008), 25/26, Seite 4442-4451
A thorough theoretical understanding of the interaction of excitons and surface plasmon polaritons (SPP) in metal-semiconductor hybrid structures is of fundamental importance for the design of SPP-based devices. A theory to describe SPP-exciton interaction in a periodic multilayer film system is presented and demonstrated. In a hybrid system of gold nanowires on top of a GaAs/AlGaAs quantum well (QW), our calculations show the formation of coupled SPP-exciton modes. These are predicted to be observable in reflection spectra and by near-field scanning optical microscopy.
Physica status solidi / B Berlin : Wiley-VCH, 1971 245(2008), 6, Seite 1071-1075
Auch als elektronisches Dokument verfügbar: http://prl.aps.org/pdf/PRL/v101/i11/e116801
We report measurements of a coherent coupling between surface plasmon polaritons (SPP) and quantum well excitons in a hybrid metal-semiconductor nanostructure. The hybrid structure is designed to optimize the radiative exciton-SPP interaction which is probed by low-temperature, angle-resolved, far-field reflectivity spectroscopy. As a result of the coupling, a significant shift of ~7 meV and an increase in broadening by ~4 meV of the quantum well exciton resonance are observed. The experiments are corroborated by a phenomenological coupled-oscillator model predicting coupling strengths as large as 50 meV in structures with optimized detunings between the coupled exciton and SPP resonances. Such a strong interaction can, e.g., be used to enhance the luminescence yield of semiconductor quantum structures or to amplify SPP waves.
Physical review letters Ridge, NY : American Physical Society, 1958 101(2008), 11, Seite 116801-1-116801-4