ISBN 9783843937948

978-3-8439-3794-8, Reihe Physik

Hoan Vu
Rolled-up plasmonic metamaterials coupled to quantum-well emitters

112 Seiten, Dissertation Universität Hamburg (2017), Softcover, A5

Zusammenfassung / Abstract

Within the scope of this thesis rolled-up plasmonic nanostructures are fabricated and investigated. Based on the concept of strain-induced self-rolling of semiconductor layers, microtubes containing tailor-made metal structures are realized. The coupling of tunable plasmonic systems to integrated quantum-well emitters is studied experimentally and by electromagnetic simulations.

A material exhibiting hyperbolic dispersion is realized. Stacked metal and semiconductor layers are fabricated by rolling-up metal films into the microtube's wall. This structure supports coupled surface plasmon polaritons that account for the optical properties. The integrated quantum-well emitters couple to the layered system and an enhancement of the quantum well’s spontaneous emission rate is observed for a specific ratio of metal and semiconductor layer thicknesses. By means of electromagnetic simulations, the rate enhancement can be assigned to the crossover from elliptic to hyperbolic dispersion.

The rolling-up fabrication allows to create a freestanding semiconductor layer with adjoined periodic metal structures. This structure supports waveguide-plasmon polaritons, which are excited and coupled into the semiconductor layer by the metallic grating. A coupling of quantum-well emission to the metallic system is observed for a specific grating’s bar width and electromagnetic simulations reveal that the coupling is accounted for by the excitation of waveguide-plasmon polaritons.

A rolled-up hybrid nanoantenna-emitter system is constructed. Metallic nanocuboids supporting localized surface plasmons are stacked into the wall of a microtube and serve as a plasmonic nanoantenna, whose resonance is tunable by changing the lateral distance of the cuboids. The nanoantenna can change the light emission of the integrated quantum well and a distinct coupling of antenna and emitter is observed for a particular nanoantenna geometry.