Influence of spin-orbit split-off band on optical properties of spherical semiconductor nanocrystals. The case of CdTe.

Pierre Lefebvre (1) , Tristan Richard (1) , Henry Mathieu (1) , Jacques Allègre (1)

1 GES - Groupe d'étude des semiconducteurs

The multiband envelope-function formalism, including the effects of finite spin-orbit splitting energy Δ, is used to calculate valence-band confined states in spherical semiconductor nanocrystallites. A compact analytical formulation of the necessary equations is proposed. In the particular case of CdTe, despite the large value of Δ, the split-off band has a sizeable influence on the fundamental interband transition, which is found dipole-forbidden, by symmetry. This result cannot be accounted for by usual models in which the influence of the split-off band is a priori neglected, when Δ is large. The consequences of basic assumptions on this prediction, which should have important consequences on intrinsic luminescence, are discussed.

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

Pierre Lefebvre, Tristan Richard, Henry Mathieu, Jacques Allègre. Influence of spin-orbit split-off band on optical properties of spherical semiconductor nanocrystals. The case of CdTe.. Solid State Communications, 1996, 98 (4), pp.303. ⟨10.1016/0038-1098(96)00044-0⟩. ⟨hal-01233756⟩