Giant excitonic exchange splitting in Si nanowires: First-principles calculations

Maurizia Palummo,1,2 Federico Iori,1,3 Rodolfo Del Sole,1,2 and Stefano Ossicini1,4 1European Theoretical Spectroscopy Facility (ETSF) 2CNR-INFM-SMC, Dipartimento di Fisica, Universita “Tor Vergata,” Via della Ricerca Scientifica 1, 00133 Roma, Italy 3Laboratoire des Solides Irradies, Ecole Polytechnique, F-91128 Palaiseau, France 4CNR-INFM-S3, Dipartimento di Scienze e Metodi dell’ Ingegneria, Universita di Modena e Reggio Emilia, via Amendola 2 Pad. Morselli, I-42100 Reggio Emilia, Italy Received 20 July 2009; revised manuscript received 9 December 2009; published 9 March 2010