Nanotechnology : Creating Non-linear Optics

Introduction
Lithium noibate has been used traditionally in optical devices for many years. With the  advent of Nanoscale Physics, there is a possibility that implanting this material with Au may result in an enhanced third-order susceptibility in the surface plasmon resonance with pico-second response time and hence applications in better and faster optical switching devices. The implanted crystals will be optically characterised by measuring the non-linear absorption and refractive index.

High Energy Gold Implantation Procedure
These implants were performed at the EN Tandem Accelerator of the Schonland Research Institute for Nuclear Sciences at the Wits University.


 
Chacterisation
The Ion Beam Analysis was performed at the EN Tandem Accelerator of the Schonland Research Institute for Nuclear Sciences at the Wits University.

RBS using a 8 MeV Li beam to evaluate the buried layer of gold was performed.

This enabled the Au buried layer to be identified (see red peak below), separated from the host material (yellow area).

The measurements were performed in the Ion-uProbe facility, with a Li beam spot of 20um diameter. Spot analyses could then be performed.

 
Schematic of measurement


 
Typical RBS spectrum
Note the well separated gold peak (red), even though its a buried layer.

Amoricium calibration spectrum
The energy resolution is good enough to resolve clearly 3 separate peaks.