The purpose of this research is to improve a quantum dot based single photon source (SPS) by double-pass filtering weak coherent light pulses. This means that a second excitation of the quantum dot...Show moreThe purpose of this research is to improve a quantum dot based single photon source (SPS) by double-pass filtering weak coherent light pulses. This means that a second excitation of the quantum dot is done with light that has previously been scattered off the quantum dot. A double pass through a quantum dot in a cavity has never been done before and this thesis provides the first steps towards this. This could eventually lead to improvements in photonic quantum gates and therefore also in the field of quantum circuits. The polarization configuration of the setup plays an important role because we have to excite the quantum dot efficiently, and we want to filter out all (coherent) background light. The measurements show evidence that this novel scheme is feasible, however we have not yet established a higher single photon purity with respect to the single pass system, which will be subject to future research.Show less
