الفهرس 
Surface PlasmonOnly 14 pages are availabe for public view
 |  | from | 129 |  |  |
| | | from | 129 | | |
Abstract
We have studied the coupling of propagating Surface Plasmon Polariton (SPP) on silver film (Ag) and exciton in CdS quantum dots (QDs). We employed the Kretschmann configuration of the attenuated total reflection (ATR) to propagate the SPP on silver film of thickness 47.5nm at three different wavelengths 448nm, 532nm, and 632nm. The CdS QDs of a particular size (~ 3.5nm) according to Effective Mass Approximation (EMA) have been chemical synthesized due to the surface plasmon frequency. The complex dielectric constant of the Ag films were determined from the ATR measurements as well as the dispersion relation of the SP.High Resolution Transmission Electron Microscope (HRTEM), Scan Tunneling Microscope (STM) and Scan Tunneling Spectroscopy (STS) were employed to confirm the size of CdS QD as well as the band gap of the QD. At the selected CdS QD size it was possible to complete the exciton to the Ag film SP. The coupling has been observed at resonance as two branching dip in the ATR spectra indicating a momentum shift. This is the first time to observe that a momentum transfer that would occure Rabi interaction between SPP and exciton. This may be a result of using a high resolution angular scan (± 0.005o). Three different linker molecules (trioctylphosphine oxide, hexadecylamine), (Pyridine), (Tri-butylamine) have been used as individual surfactant that were confirmed by Fourier Transform Infrared Spectroscopy (FTIR) for each case to vary the distance between the interacting SPP and the CdS QD exciton. The coupling strength varied with the length of the linker.