First-principles design of efficient solar cells using two-dimensional arrays of core-shell and layered SiGe nanowires
PHYSICAL REVIEW B, vol.83, no.3, 2011 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 83 Issue: 3
- Publication Date: 2011
- Doi Number: 10.1103/physrevb.83.035317
- Journal Name: PHYSICAL REVIEW B
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Middle East Technical University Affiliated: No
Abstract
Research for third generation solar cell technology has been driven by the need to overcome the efficiency and cost problems encountered by current crystalline Si- and thin-film-based solar cells. Using first-principles methods, Ge/Si and Si/Ge core/shell and Si-Ge layered nanowires are shown to possess the required qualities for an efficient use in photovoltaic applications. We investigate the details of their band structure, effective mass, absorption property, and charge-carrier localization. The strong charge separation and improved absorption in the visible spectrum indicate a remarkable quantum efficiency that, combined with new designs, compares positively with bulk Si.