Electronic and optical properties of silicon nanocrystals are calculated and discussed within a semiempirical tight-binding approach, which allows to study systems composed of thousands of atoms. Oscillator strengths, frequency-dependent optical absorption cross sections, and static dielectric constants are investigated for both spherical and ellipsoidal nanocrystals, with the aim of pointing out their size- and shape-dependent features. We show that the anisotropy of the optical functions follows the nanocrystal shape, and a comparison is discussed between very elongated structures and quantum wires.
Tight-binding calculation of the optical absorption cross section of spherical and ellipsoidal silicon nanocrystals / F., Trani; G., Cantele; Ninno, Domenico; Iadonisi, Giuseppe. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - STAMPA. - 72:(2005), pp. 75423-1-75423-8. [10.1103/PhysRevB.72.075423]
Tight-binding calculation of the optical absorption cross section of spherical and ellipsoidal silicon nanocrystals
NINNO, DOMENICO;IADONISI, GIUSEPPE
2005
Abstract
Electronic and optical properties of silicon nanocrystals are calculated and discussed within a semiempirical tight-binding approach, which allows to study systems composed of thousands of atoms. Oscillator strengths, frequency-dependent optical absorption cross sections, and static dielectric constants are investigated for both spherical and ellipsoidal nanocrystals, with the aim of pointing out their size- and shape-dependent features. We show that the anisotropy of the optical functions follows the nanocrystal shape, and a comparison is discussed between very elongated structures and quantum wires.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.