First Principle Calculations of Positron Annihilation in CdSe Quantum Dots
Abstract
Experimental observations of positron annihilation spectra in CdSe quantum dot systems have shown clear evidence of size effects. We are performing first principle computations to attempt to understand these observations. Our simulations are intented to study the smearing of momentum density near the boundary of the Jones zone, which is expected to be proportional to the widening of the band gap with decreasing size. This effect shows up in the Doppler broadening spectra. Affinity, momentum density and lifetime predictions are being carried out using Density Functional Theory within the GGA scheme [1]. [1] B. Barbiellini, M. J. Puska, T. Korhonen, A. Harju, T. Torsti and R. M. Nieminen, Phys. Rev. B 53 (1996) 16201
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARQ24016B