Picosecond dynamics of free and bound excitons in doped diamond.

Julien Barjon (1) , Pierre Valvin (2) , Christelle Brimont (2) , Pierre Lefebvre (2) , Ovidiu Brinza (3) , Alexandre Tallaire (3) , Jocelyn Achard (3) , François Jomard (1) , Marie-Amandine Pinault-Thaury (1)

1 GEMAC - Groupe d'Etude de la Matière Condensée
2 L2C - Laboratoire Charles Coulomb
3 LSPM - Laboratoire des Sciences des Procédés et des Matériaux

The dynamics of the free-exciton capture by boron acceptors and phosphorus donors in diamond is observed in the picosecond range by time-resolved photoluminescence experiments at low temperature. The formation of boron-bound excitons is observed with a delay of 410 ps after the formation of free excitons. For phosphorus, this delay is 120 ps. This is the result of the free-exciton capture by B0 and P0 impurities. The lifetimes of boron- and phosphorus-bound excitons are measured and found to be equal to 270 and 70 ps, respectively. These values are about four orders of magnitude shorter than for the same impurities in silicon. Ei being the ionization energy of dopants, these results scale well with the E4i dependence of the Auger recombination rate expected for bound excitons in indirect band-gap semiconductors.

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

Julien Barjon, Pierre Valvin, Christelle Brimont, Pierre Lefebvre, Ovidiu Brinza, et al.. Picosecond dynamics of free and bound excitons in doped diamond.. Physical Review B, 2016, 93 (11), pp.115202. ⟨10.1103/PhysRevB.93.115202⟩. ⟨hal-01287753⟩