Surface and confinement effects on the optical and structural properties of silicon nanocrystals

Stefano Ossicini; Rita Magri; Elena Degoli; Marcello Luppi; Eleonora Luppi

doi:10.1117/12.508481

14 November 2003 Surface and confinement effects on the optical and structural properties of silicon nanocrystals

Stefano Ossicini, Rita Magri, Elena Degoli, Marcello Luppi, Eleonora Luppi

Proceedings Volume 5222, Nanocrystals, and Organic and Hybrid Nanomaterials; (2003) https://doi.org/10.1117/12.508481
Event: Optical Science and Technology, SPIE's 48th Annual Meeting, 2003, San Diego, California, United States

Abstract

In this work we investigate, by first-principles calculations, the structural, electronic and optical properties of: (1) oxygenated silicon-based nanoclusters of different sizes in regime of multiple oxidation at the surface, and (2) hydrogenated Si nanoclusters (H-Si-nc) in their ground and excited state configurations. Structural relaxations have been fully taken into account in all cases through total energy pseudopotential calculations within density functional theory. In the first case we have varied systematically the number of Si=O bonds at the cluster surface and found a nonlinear reduction of the energy gap with the Si=O bond number. A saturation limit is reached, which allows us to provide a consistent interpretation of the photoluminescence (PL) redshift observed in oxidized porous silicon samples. Our results help also to explain some very recent findings on the single silicon quantum dot photoluminescence bandwidth. In the second case, after a preliminary study of the clusters stability, the properties of the ground and excited states have been compared varying the cluster dimensions from 1 to 29 Si atoms. Ab-initio calculations of the Stokes shift as a function of the cluster dimension will be presented. A structural model linked to the four level scheme recently invoked to explain the experimental outcomes relative to the observed optical gain in Si-nc embedded in a SiO₂ matrix will be also suggested.

Citation Download Citation

Stefano Ossicini, Rita Magri, Elena Degoli, Marcello Luppi, and Eleonora Luppi "Surface and confinement effects on the optical and structural properties of silicon nanocrystals", Proc. SPIE 5222, Nanocrystals, and Organic and Hybrid Nanomaterials, (14 November 2003); https://doi.org/10.1117/12.508481

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
11 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Silicon

Hydrogen

Chemical species

Nanocrystals

Oxygen

Absorption

Crystals

Show All Keywords

Keywords/Phrases

Search In:

Publication Years