High internal electric field in a graded-width InGaN/GaN quantum well: Accurate determination by time-resolved photoluminescence spectroscopy.

Pierre Lefebvre (1) , Aurélien Morel (1) , Mathieu Gallart (1) , Thierry Taliercio (1) , Jacques Allègre (1) , Bernard Gil (1) , Henry Mathieu (1) , Benjamin Damilano (2) , Nicolas Grandjean (2) , Jean Massies (2)

1 GES - Groupe d'étude des semiconducteurs
2 CRHEA - Centre de recherche sur l'hétéroepitaxie et ses applications

Time-resolvedphotoluminescence (PL), at T=8 K, is used to study a graded-width InGaN/GaN quantum well. Across the sample, the well width continuously varies from ∼5.5 to 2.0 nm corresponding to PL peak energies varying between 2.0 and 2.9 eV and to PL decay rates covering four orders of magnitude. The plot of decay times versus PL energies is very well fitted by a calculation of the electron–hole recombination probability versus well width. The only fitting parameter is the electric field in the well, which we find equal to 2.45±0.25 MV/cm, in excellent agreement with experimental Stokes shifts for this type of samples.

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Optique [physics.optics]; Micro et nanotechnologies/Microélectronique; Optique / photonique

Pierre Lefebvre, Aurélien Morel, Mathieu Gallart, Thierry Taliercio, Jacques Allègre, et al.. High internal electric field in a graded-width InGaN/GaN quantum well: Accurate determination by time-resolved photoluminescence spectroscopy.. Applied Physics Letters, 2001, 78 (9), pp.1252. ⟨10.1063/1.1351517⟩. ⟨hal-01303203⟩