Photoluminescence polarized spectra

We studied electric field effects on optical properties of CdSe/ZnS nanorods integrated in thin films sandwiched between transparent electrodes. It was demonstrated that P-polarized component of the photoluminescence of CdSe/ZnS nanorods is quenched stronger by external electric field than the S-polarized component. Quantum dots are more sensitive to external electric field than the nanorods. A mechanism of external electric field influence on the luminescence spectrum of semiconductor nanorods is discussed. 

FIGURE 2.1.26 -Polarized absorption spectrum (a), photoluminescence spectrum (PL), cw luminescence excitation spectrum (PLE) — monitored at 570 nm (dashed line) and 620 nm (dotted line) — and excitation spectrum of the microsecond luminescence transient induced by -polarized light (open circles) in rubrene single crystals. (From Najafov, H. et al., Phys. Rev. Lett., 96, 056604, 2006.)... 

The luminescence properties of siloxene have now been studied in great detail. A typical siloxene PL spectrum is shown at the bottom of Figure 15.4 (b). It has a maximum in the yellow-green spectral range at around 2.4 eV. At low temperatures, a radiative lifetime of 10 ns and a polarization memory were observed. These properties and the small Stokes shift between the photoluminescence and its excitation spectra provide experimental evidence for the hypothesis that siloxene does indeed have a direct band gap. Details of the excited states in siloxene leading to the luminescence have also been obtained from measurements of optically detected magnetic resonance... 

Fig. 6.12 Right (PLr) and left (PLl) circularly polarized photoluminescence from a light-emitting chiral nematic liquid crystal, whose photoluminescence spectrum overlap its stop-band. The dotted line shows the stop-band, where transmission of right-hand circularly polarized light is forbidden...

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