Time-resolved photoluminescence of n-doped SrTiO3

Temperature dependence of continuum and time resolved photoluminescence of germanium nanostructures

  Germanium nanostructures were generated in the post annealed germanium oxide thin films. Visible and near infrared photoluminescence bands were observed in the samples annealed at 350°C and 400°C, respectively. These different luminescence ranges are attributed to the presence of the defects in oxide matrix and quantum confinement effect in the germanium nanostructures, respectively. Decay ti...

Isotope effect in superconducting n-doped SrTiO3

We report the influence on the superconducting critical temperature Tc in doped SrTiO3 of the substitution of the natural 16O atoms by the heavier isotope 18O. We observe that for a wide range of doping this substitution causes a strong (~50%) enhancement of Tc. Also the magnetic critical field Hc2 is increased by a factor ~2. Such a strong impact on Tc and Hc2, with a sign opposite to conventi...

Time-resolved photoluminescence measurement on polythiophene derivative

We measured the time-resolved photoluminescence (PL) on a film of a polythiophene derivative to investigate the formation and relaxation processes of a self-trapped exciton (STE). On the highand low-energy sides of the PL spectrum, we observed an ultrafast decay component emitted during the STE formation. We also found that PL of the derivative originates from two STE states with opposite symme...

Microsecond spin-flip times in n-GaAs measured by time-resolved polarization of photoluminescence

We have observed microsecond spin-flip times in lightly doped n-GaAs, by measuring the photoluminescence polarization in the time domain with pump and probe pulses. Times up to 1.4 ms have been measured. Our results as a function of magnetic field indicate three regions governing the spin relaxation: a low field region, where spin-flip times increase due to suppression of the nuclear hyperfine ...

Time-resolved photoluminescence studies of Al x Ga 1x N alloys