Correlation spectrosopy of single emitters : fundamental studies and applications related to quantum optics and life science

Sammanfattning: Correlation analysis and correlation spectroscopy has eversince the first developments, to characterise light emittingprocesses and biomolecular dynamics, continued to extend itspractical applicability. Today, correlation spectroscopy can beused in life science to study dynamical processes even at thesingle molecule level. Correlation analysis can in one of itsextreme be applied to investigate single photon processes fromsolid-state emitters. This thesis is an account of my studiesof fluorescent emitter related to quantum optics and lifescience. It presents some fundamental results and discussesapplicationsof emitters like single quantum dots or singledyes attached to biomolecules. The studies were performed bythe means of correlation analysis and correlation spectroscopyon self-made optical setups. One task of this thesis was todevelop fluorescence correlation spectroscopy for ultravioletexcitation and emission. With ultraviolet excitation thenatural intrinsic chromophores of certain nucleotides and aminoacids can be used. No external labelling of biomolecules couldbecome a reality using ultraviolet excitation and emission. Asecond task was to apply correlation spectroscopy to performhigh spatial-resolution flow profiling and trafficking ofsingle dye-labeled biomolecules in microstructured channels.Future transports effects, flow monitoring, flow profiling andprolonged fluorescence detection in artificial microstructuresor in cells, could benefit from this application. An additionaltask was to apply correlation spectroscopy to so-calledmicroarrays for parallel acquisition of dynamical data at thesingle molecule level. Parallel excitation and detection wasachieved with the use of diffractive optical elements andintegrated semiconductor single-photon sensitive detectors. Thecurrent throughput rate in biological diagnostic or screeninganalysis could be increased dramatically with implementation ofthis parallel confocal excitation and detection technique. Yetanother task of this thesis was to investigations single-photongeneration by InAs-semiconductor quantum dots. We show that aquantum dots can be used for single-photon generation ondemand. Besides the single-photon generation in quantum dots,the possibility of two-photon generation, and generation ofentangled photon-pair, has also been investigated.