title: Tight-binding calculations of the optical response of optimally P-doped Si nanocrystals: a model for localized surface plasmon resonance.
abstract: We present tight-binding calculations in the random-phase approximation of the optical response of Silicon nanocrystals (Si NCs) ideally doped with large concentrations of phosphorus (P) atoms. A collective response of P-induced electrons is demonstrated, leading to localized surface plasmon resonance (LSPR) when a Si NC contains more than ≈10 P atoms. The LSPR energy varies not only with doping concentration but also with NC size due to size-dependent screening by valence electrons. The simple Drude-like behavior is recovered for NC size above 4 nm. Si NCs containing a large number of deep defects in place of hydrogenic impurities do not give rise to LSPR.
authors.affiliation: State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Pi
authors.forename: Christophe
authors.initials: C
authors.lastname: Delerue
mesh_terms: D008962:Models, Theoretical; D053758:Nanoparticles / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D010758:Phosphorus; D012825:Silicon